Auto merge of #9532 - nox:dedup-heapsize, r=Manishearth

Say farewell to in-tree HeapSizeOf

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82 files changed, 423 insertions, 878 deletions

diff --git a/components/canvas_traits/Cargo.toml b/components/canvas_traits/Cargo.toml
index 4fc4be5afc5..83bb07f7076 100644
--- a/components/canvas_traits/Cargo.toml
+++ b/components/canvas_traits/Cargo.toml
@@ -35,7 +35,9 @@ path = "../plugins"
 path = "../util"
 
 [dependencies]
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
 euclid = {version = "0.6.1", features = ["plugins"]}
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 serde_macros = "0.6"
 
diff --git a/components/canvas_traits/lib.rs b/components/canvas_traits/lib.rs
index d54530b94fd..4dc0a5904f8 100644
--- a/components/canvas_traits/lib.rs
+++ b/components/canvas_traits/lib.rs
@@ -7,13 +7,14 @@
 #![feature(custom_derive)]
 #![feature(nonzero)]
 #![feature(plugin)]
-#![plugin(serde_macros, plugins)]
+#![plugin(heapsize_plugin, plugins, serde_macros)]
 
 extern crate azure;
 extern crate core;
 extern crate cssparser;
 extern crate euclid;
 extern crate gfx_traits;
+extern crate heapsize;
 extern crate ipc_channel;
 extern crate layers;
 extern crate offscreen_gl_context;
@@ -40,7 +41,6 @@ use std::default::Default;
 use std::fmt;
 use std::str::FromStr;
 use std::sync::mpsc::Sender;
-use util::mem::HeapSizeOf;
 
 #[derive(Clone, Deserialize, Serialize)]
 pub enum FillRule {
diff --git a/components/compositing/Cargo.toml b/components/compositing/Cargo.toml
index 965547b82db..937bc11e3bb 100644
--- a/components/compositing/Cargo.toml
+++ b/components/compositing/Cargo.toml
@@ -91,7 +91,7 @@ gleam = "0.2"
 euclid = {version = "0.6.1", features = ["plugins"]}
 serde = "0.6"
 serde_macros = "0.6"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 
 [target.x86_64-apple-darwin.dependencies]
 core-graphics = "0.2"
diff --git a/components/devtools/Cargo.toml b/components/devtools/Cargo.toml
index b825ef9bc48..36567380d14 100644
--- a/components/devtools/Cargo.toml
+++ b/components/devtools/Cargo.toml
@@ -25,7 +25,7 @@ git = "https://github.com/servo/ipc-channel"
 [dependencies]
 hyper = { version = "0.7", features = [ "serde-serialization" ] }
 log = "0.3"
-time = "0.1"
 rustc-serialize = "0.3"
 serde = "0.6"
 serde_macros = "0.6"
+time = "0.1"
diff --git a/components/devtools_traits/Cargo.toml b/components/devtools_traits/Cargo.toml
index c0a282226f7..115ab732691 100644
--- a/components/devtools_traits/Cargo.toml
+++ b/components/devtools_traits/Cargo.toml
@@ -20,11 +20,13 @@ git = "https://github.com/servo/ipc-channel"
 path = "../plugins"
 
 [dependencies]
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 hyper = { version = "0.7", features = [ "serde-serialization" ] }
 time = "0.1"
 rustc-serialize = "0.3"
 bitflags = "0.3"
 serde = "0.6"
 serde_macros = "0.6"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 
diff --git a/components/devtools_traits/lib.rs b/components/devtools_traits/lib.rs
index 81644badc44..8408a79b197 100644
--- a/components/devtools_traits/lib.rs
+++ b/components/devtools_traits/lib.rs
@@ -13,10 +13,11 @@
 #![deny(unsafe_code)]
 
 #![feature(custom_derive, plugin)]
-#![plugin(serde_macros, plugins)]
+#![plugin(heapsize_plugin, serde_macros)]
 
 #[macro_use]
 extern crate bitflags;
+extern crate heapsize;
 extern crate hyper;
 extern crate ipc_channel;
 extern crate msg;
@@ -36,7 +37,6 @@ use std::net::TcpStream;
 use time::Duration;
 use time::Tm;
 use url::Url;
-use util::mem::HeapSizeOf;
 
 // Information would be attached to NewGlobal to be received and show in devtools.
 // Extend these fields if we need more information.
diff --git a/components/gfx/Cargo.toml b/components/gfx/Cargo.toml
index 4306c3232ac..874e95d591a 100644
--- a/components/gfx/Cargo.toml
+++ b/components/gfx/Cargo.toml
@@ -14,6 +14,8 @@ bitflags = "0.3"
 euclid = {version = "0.6.1", features = ["plugins"]}
 fnv = "1.0"
 harfbuzz-sys = "0.1"
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 lazy_static = "0.1"
 libc = "0.2"
 log = "0.3"
@@ -23,10 +25,10 @@ rustc-serialize = "0.3"
 serde = "0.6"
 serde_macros = "0.6"
 smallvec = "0.1"
-string_cache = "0.2"
+string_cache = {version = "0.2.7", features = ["heap_size"]}
 time = "0.1.12"
 unicode-script = { version = "0.1", features = ["harfbuzz"] }
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 servo-skia = "0.20130412.0"
 
 [dependencies.plugins]
diff --git a/components/gfx/display_list/mod.rs b/components/gfx/display_list/mod.rs
index b6565753f36..96c953d3dfe 100644
--- a/components/gfx/display_list/mod.rs
+++ b/components/gfx/display_list/mod.rs
@@ -22,6 +22,7 @@ use euclid::approxeq::ApproxEq;
 use euclid::num::Zero;
 use euclid::{Matrix2D, Matrix4, Point2D, Rect, SideOffsets2D, Size2D};
 use gfx_traits::{color, LayerId, LayerKind, ScrollPolicy};
+use heapsize::HeapSizeOf;
 use msg::constellation_msg::PipelineId;
 use net_traits::image::base::Image;
 use paint_context::PaintContext;
@@ -41,7 +42,6 @@ use text::glyph::CharIndex;
 use util::cursor::Cursor;
 use util::geometry::MAX_RECT;
 use util::linked_list::prepend_from;
-use util::mem::HeapSizeOf;
 use util::opts;
 use util::print_tree::PrintTree;
 use util::range::Range;
@@ -1256,8 +1256,8 @@ pub struct GradientDisplayItem {
 
 impl HeapSizeOf for GradientDisplayItem {
     fn heap_size_of_children(&self) -> usize {
+        use heapsize::heap_size_of;
         use libc::c_void;
-        use util::mem::heap_size_of;
 
         // We can't measure `stops` via Vec's HeapSizeOf implementation because GradientStop isn't
         // defined in this module, and we don't want to import GradientStop into util::mem where
diff --git a/components/gfx/font_context.rs b/components/gfx/font_context.rs
index 1011d40112b..6fc010fedf3 100644
--- a/components/gfx/font_context.rs
+++ b/components/gfx/font_context.rs
@@ -13,6 +13,7 @@ use font::SpecifiedFontStyle;
 use font::{Font, FontGroup};
 use font_cache_thread::FontCacheThread;
 use font_template::FontTemplateDescriptor;
+use heapsize::HeapSizeOf;
 use platform::font::FontHandle;
 use platform::font_context::FontContextHandle;
 use platform::font_template::FontTemplateData;
@@ -28,7 +29,6 @@ use std::sync::atomic::{AtomicUsize, Ordering, ATOMIC_USIZE_INIT};
 use string_cache::Atom;
 use style::computed_values::{font_style, font_variant};
 use util::cache::HashCache;
-use util::mem::HeapSizeOf;
 
 #[cfg(any(target_os = "linux", target_os = "android", target_os = "windows"))]
 fn create_scaled_font(template: &Arc<FontTemplateData>, pt_size: Au) -> ScaledFont {
diff --git a/components/gfx/lib.rs b/components/gfx/lib.rs
index c088e7e9b97..8bc6f8c8b4a 100644
--- a/components/gfx/lib.rs
+++ b/components/gfx/lib.rs
@@ -15,6 +15,7 @@
 #![feature(str_char)]
 #![feature(unique)]
 
+#![plugin(heapsize_plugin)]
 #![plugin(plugins)]
 #![plugin(serde_macros)]
 
@@ -45,6 +46,7 @@ extern crate gfx_traits;
 // shapers. For now, however, this is a hard dependency.
 extern crate harfbuzz_sys as harfbuzz;
 
+extern crate heapsize;
 extern crate ipc_channel;
 extern crate layers;
 #[macro_use]
diff --git a/components/gfx/platform/freetype/font_context.rs b/components/gfx/platform/freetype/font_context.rs
index 05cbd0675f6..1ed40300639 100644
--- a/components/gfx/platform/freetype/font_context.rs
+++ b/components/gfx/platform/freetype/font_context.rs
@@ -10,10 +10,10 @@ use freetype::freetype::FT_Library;
 use freetype::freetype::FT_Memory;
 use freetype::freetype::FT_New_Library;
 use freetype::freetype::struct_FT_MemoryRec_;
+use heapsize::{HeapSizeOf, heap_size_of};
 use libc::{c_long, c_void};
 use std::ptr;
 use std::rc::Rc;
-use util::mem::{HeapSizeOf, heap_size_of};
 
 // We pass a |User| struct -- via an opaque |void*| -- to FreeType each time a new instance is
 // created. FreeType passes it back to the ft_alloc/ft_realloc/ft_free callbacks. We use it to
diff --git a/components/gfx/platform/macos/font_context.rs b/components/gfx/platform/macos/font_context.rs
index e260f84b17b..e728b62aebd 100644
--- a/components/gfx/platform/macos/font_context.rs
+++ b/components/gfx/platform/macos/font_context.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use util::mem::HeapSizeOf;
+use heapsize::HeapSizeOf;
 
 #[derive(Clone, Debug)]
 pub struct FontContextHandle {
diff --git a/components/gfx_traits/Cargo.toml b/components/gfx_traits/Cargo.toml
index d6e132caa8f..0f7165f3494 100644
--- a/components/gfx_traits/Cargo.toml
+++ b/components/gfx_traits/Cargo.toml
@@ -26,5 +26,7 @@ path = "../util"
 
 [dependencies]
 euclid = {version = "0.6.1", features = ["plugins"]}
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 serde = "0.6"
 serde_macros = "0.6"
diff --git a/components/gfx_traits/lib.rs b/components/gfx_traits/lib.rs
index 980e850b014..84e74038e40 100644
--- a/components/gfx_traits/lib.rs
+++ b/components/gfx_traits/lib.rs
@@ -3,13 +3,14 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #![feature(custom_derive, plugin)]
-#![plugin(plugins, serde_macros)]
+#![plugin(heapsize_plugin, plugins, serde_macros)]
 
 #![crate_name = "gfx_traits"]
 #![crate_type = "rlib"]
 
 extern crate azure;
 extern crate euclid;
+extern crate heapsize;
 extern crate layers;
 extern crate msg;
 extern crate serde;
diff --git a/components/layout/Cargo.toml b/components/layout/Cargo.toml
index ed2f70cb494..9c494dbc07c 100644
--- a/components/layout/Cargo.toml
+++ b/components/layout/Cargo.toml
@@ -55,20 +55,22 @@ git = "https://github.com/servo/ipc-channel"
 
 [dependencies]
 app_units = {version = "0.2", features = ["plugins"]}
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
-log = "0.3"
-fnv = "1.0"
 bitflags = "0.3"
-rustc-serialize = "0.3"
-libc = "0.2"
-selectors = "0.4.1"
-smallvec = "0.1"
-string_cache = "0.2"
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
 euclid = {version = "0.6.1", features = ["plugins"]}
+fnv = "1.0"
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
+libc = "0.2"
+log = "0.3"
+rustc-serialize = "0.3"
+selectors = {version = "0.4.1", features = ["heap_size"]}
 serde = "0.6"
-serde_macros = "0.6"
 serde_json = "0.5"
+serde_macros = "0.6"
+smallvec = "0.1"
+string_cache = {version = "0.2.7", features = ["heap_size"]}
 time = "0.1"
 unicode-bidi = "0.2"
 unicode-script = { version = "0.1", features = ["harfbuzz"] }
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/components/layout/context.rs b/components/layout/context.rs
index 9657590be3f..134a6f03b2b 100644
--- a/components/layout/context.rs
+++ b/components/layout/context.rs
@@ -14,6 +14,7 @@ use fnv::FnvHasher;
 use gfx::font_cache_thread::FontCacheThread;
 use gfx::font_context::FontContext;
 use gfx_traits::LayerId;
+use heapsize::HeapSizeOf;
 use ipc_channel::ipc::{self, IpcSender};
 use net_traits::image::base::Image;
 use net_traits::image_cache_thread::{ImageCacheChan, ImageCacheThread, ImageResponse, ImageState};
@@ -27,7 +28,6 @@ use std::sync::{Arc, Mutex};
 use style::context::{LocalStyleContext, SharedStyleContext, StyleContext};
 use style::matching::{ApplicableDeclarationsCache, StyleSharingCandidateCache};
 use url::Url;
-use util::mem::HeapSizeOf;
 use util::opts;
 
 struct LocalLayoutContext {
diff --git a/components/layout/layout_thread.rs b/components/layout/layout_thread.rs
index 206bfe4c82d..2b1950d88ce 100644
--- a/components/layout/layout_thread.rs
+++ b/components/layout/layout_thread.rs
@@ -28,6 +28,7 @@ use gfx::font_cache_thread::FontCacheThread;
 use gfx::font_context;
 use gfx::paint_thread::{LayoutToPaintMsg, PaintLayer};
 use gfx_traits::{color, Epoch, LayerId, ScrollPolicy};
+use heapsize::HeapSizeOf;
 use incremental::{LayoutDamageComputation, REFLOW, REFLOW_ENTIRE_DOCUMENT, REPAINT};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use ipc_channel::router::ROUTER;
@@ -73,7 +74,6 @@ use url::Url;
 use util::geometry::MAX_RECT;
 use util::ipc::OptionalIpcSender;
 use util::logical_geometry::LogicalPoint;
-use util::mem::HeapSizeOf;
 use util::opts;
 use util::thread;
 use util::thread_state;
diff --git a/components/layout/lib.rs b/components/layout/lib.rs
index cf0d2f18ea1..a3b78e8c4bd 100644
--- a/components/layout/lib.rs
+++ b/components/layout/lib.rs
@@ -17,6 +17,7 @@
 
 #![deny(unsafe_code)]
 
+#![plugin(heapsize_plugin)]
 #![plugin(plugins)]
 
 extern crate app_units;
@@ -30,6 +31,7 @@ extern crate euclid;
 extern crate fnv;
 extern crate gfx;
 extern crate gfx_traits;
+extern crate heapsize;
 extern crate ipc_channel;
 extern crate layout_traits;
 extern crate libc;
diff --git a/components/layout_traits/Cargo.toml b/components/layout_traits/Cargo.toml
index 4729605b282..a2c4c2fba27 100644
--- a/components/layout_traits/Cargo.toml
+++ b/components/layout_traits/Cargo.toml
@@ -31,4 +31,4 @@ git = "https://github.com/servo/ipc-channel"
 [dependencies]
 serde = "0.6"
 serde_macros = "0.6"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/components/msg/Cargo.toml b/components/msg/Cargo.toml
index 29244da4ada..129355c8ae6 100644
--- a/components/msg/Cargo.toml
+++ b/components/msg/Cargo.toml
@@ -21,11 +21,13 @@ git = "https://github.com/servo/ipc-channel"
 path = "../plugins"
 
 [dependencies]
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
 bitflags = "0.3"
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
+euclid = {version = "0.6.1", features = ["plugins"]}
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 hyper = { version = "0.7", features = [ "serde-serialization" ] }
 rustc-serialize = "0.3.4"
-euclid = {version = "0.6.1", features = ["plugins"]}
 serde = "0.6"
 serde_macros = "0.6"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/components/msg/constellation_msg.rs b/components/msg/constellation_msg.rs
index 2ce14039a15..adefb76010c 100644
--- a/components/msg/constellation_msg.rs
+++ b/components/msg/constellation_msg.rs
@@ -16,7 +16,6 @@ use std::cell::Cell;
 use std::fmt;
 use url::Url;
 use util::geometry::{PagePx, ViewportPx};
-use util::mem::HeapSizeOf;
 use webdriver_msg::{LoadStatus, WebDriverScriptCommand};
 
 #[derive(Deserialize, Serialize)]
diff --git a/components/msg/lib.rs b/components/msg/lib.rs
index 3b5c99b8f3c..febf188fd77 100644
--- a/components/msg/lib.rs
+++ b/components/msg/lib.rs
@@ -3,11 +3,12 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #![feature(custom_attribute, custom_derive, plugin)]
-#![plugin(serde_macros, plugins)]
+#![plugin(heapsize_plugin, serde_macros, plugins)]
 
 #[macro_use]
 extern crate bitflags;
 extern crate euclid;
+extern crate heapsize;
 extern crate hyper;
 extern crate ipc_channel;
 extern crate layers;
diff --git a/components/net/Cargo.toml b/components/net/Cargo.toml
index b0bb98b779f..0c5e34874d0 100644
--- a/components/net/Cargo.toml
+++ b/components/net/Cargo.toml
@@ -38,6 +38,6 @@ cookie = "0.2"
 mime_guess = "1.1.1"
 flate2 = "0.2.0"
 uuid = "0.1.16"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 websocket = "0.14.0"
 immeta = "0.2"
diff --git a/components/net_traits/Cargo.toml b/components/net_traits/Cargo.toml
index 06d87f49e9d..d41649797c1 100644
--- a/components/net_traits/Cargo.toml
+++ b/components/net_traits/Cargo.toml
@@ -20,11 +20,13 @@ git = "https://github.com/servo/ipc-channel"
 path = "../plugins"
 
 [dependencies]
-log = "0.3"
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 hyper = { version = "0.7", features = [ "serde-serialization" ] }
 image = "0.5.0"
+log = "0.3"
 serde = "0.6"
 serde_macros = "0.6"
 stb_image = "0.2"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 websocket = "0.14.0"
diff --git a/components/net_traits/image_cache_thread.rs b/components/net_traits/image_cache_thread.rs
index 2381efbb997..8324bae8b23 100644
--- a/components/net_traits/image_cache_thread.rs
+++ b/components/net_traits/image_cache_thread.rs
@@ -6,7 +6,6 @@ use ipc_channel::ipc::{self, IpcSender};
 use msg::constellation_msg::{Image, ImageMetadata};
 use std::sync::Arc;
 use url::Url;
-use util::mem::HeapSizeOf;
 
 /// This is optionally passed to the image cache when requesting
 /// and image, and returned to the specified event loop when the
diff --git a/components/net_traits/lib.rs b/components/net_traits/lib.rs
index 654a64e811c..45d01a9818d 100644
--- a/components/net_traits/lib.rs
+++ b/components/net_traits/lib.rs
@@ -9,8 +9,9 @@
 #![feature(slice_patterns)]
 #![feature(step_by)]
 #![feature(custom_attribute)]
-#![plugin(serde_macros, plugins)]
+#![plugin(heapsize_plugin, serde_macros)]
 
+extern crate heapsize;
 extern crate hyper;
 extern crate image as piston_image;
 extern crate ipc_channel;
@@ -32,7 +33,6 @@ use msg::constellation_msg::{PipelineId};
 use serde::{Deserializer, Serializer};
 use std::thread;
 use url::Url;
-use util::mem::HeapSizeOf;
 use websocket::header;
 
 pub mod hosts;
@@ -69,6 +69,7 @@ pub enum LoadContext {
 #[derive(Clone, Deserialize, Serialize, HeapSizeOf)]
 pub struct LoadData {
     pub url: Url,
+    #[ignore_heap_size_of = "Defined in hyper"]
     pub method: Method,
     #[ignore_heap_size_of = "Defined in hyper"]
     /// Headers that will apply to the initial request only
@@ -297,6 +298,7 @@ pub struct Metadata {
     /// Final URL after redirects.
     pub final_url: Url,
 
+    #[ignore_heap_size_of = "Defined in hyper"]
     /// MIME type / subtype.
     pub content_type: Option<(ContentType)>,
 
@@ -307,6 +309,7 @@ pub struct Metadata {
     /// Headers
     pub headers: Option<Headers>,
 
+    #[ignore_heap_size_of = "Defined in hyper"]
     /// HTTP Status
     pub status: Option<RawStatus>,
 }
diff --git a/components/plugins/Cargo.toml b/components/plugins/Cargo.toml
index 172a0d3adf3..d5d1f0246b0 100644
--- a/components/plugins/Cargo.toml
+++ b/components/plugins/Cargo.toml
@@ -17,7 +17,7 @@ rev = "9dca15de3e8ea266d3e7e868c0f358ed4fa5f195"
 optional = true
 
 [dependencies]
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 
 [features]
 default = []
diff --git a/components/plugins/heap_size.rs b/components/plugins/heap_size.rs
deleted file mode 100644
index 0f8ea67fa62..00000000000
--- a/components/plugins/heap_size.rs
+++ /dev/null
@@ -1,82 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-//! Handles the auto-deriving for `#[derive(HeapSizeOf)]`
-//!
-//! This provides the `#[derive(HeapSizeOf)]` decorator, which
-//! generates a `HeapSizeOf` implementation that adds up
-//! calls to heap_size_of_children() for all the fields
-//! of a struct or enum variant.
-//!
-//! Fields marked `#[ignore_heap_size_of = "reason"]` will
-//! be ignored in this calculation. Providing a reason is compulsory.
-
-
-use syntax::ast::*;
-use syntax::attr::AttrMetaMethods;
-use syntax::codemap::Span;
-use syntax::ext::base::{Annotatable, ExtCtxt};
-use syntax::ext::build::AstBuilder;
-use syntax::ptr::P;
-use syntax_ext::deriving::generic::*;
-
-pub fn expand_heap_size(cx: &mut ExtCtxt, span: Span, mitem: &MetaItem,
-                        item: &Annotatable, push: &mut FnMut(Annotatable)) {
-    let trait_def = TraitDef {
-        is_unsafe: false,
-        span: span,
-        attributes: Vec::new(),
-        path: ty::Path::new(vec!("util", "mem", "HeapSizeOf")),
-        additional_bounds: Vec::new(),
-        generics: ty::LifetimeBounds::empty(),
-        methods: vec![
-            MethodDef {
-                name: "heap_size_of_children",
-                generics: ty::LifetimeBounds::empty(),
-                explicit_self: ty::borrowed_explicit_self(),
-                args: vec!(),
-                ret_ty: ty::Literal(ty::Path::new_local("usize")),
-                attributes: vec!(),
-                is_unsafe: false,
-                combine_substructure: combine_substructure(Box::new(heap_size_substructure))
-            }
-        ],
-        associated_types: vec![],
-    };
-    trait_def.expand(cx, mitem, item, push)
-}
-
-/// Defines how the implementation for `heap_size_of_children()` is to be generated.
-fn heap_size_substructure(cx: &mut ExtCtxt, trait_span: Span, substr: &Substructure) -> P<Expr> {
-    let fields = match *substr.fields {
-        Struct(ref fs) | EnumMatching(_, _, ref fs) => fs,
-        _ => cx.span_bug(trait_span, "impossible substructure in `#[derive(HeapSizeOf)]`")
-    };
-
-    fields.iter().fold(cx.expr_usize(trait_span, 0), |acc, ref item| {
-        if item.attrs.iter()
-               .find(|ref a| {
-                    if a.check_name("ignore_heap_size_of") {
-                        match a.node.value.node {
-                            MetaNameValue(..) => (),
-                            _ => cx.span_err(a.span, "#[ignore_heap_size_of] \
-                                                      should have an explanation, \
-                                                      e.g. #[ignore_heap_size_of = \"\"]")
-                        }
-                        true
-                    } else {
-                        false
-                    }
-                })
-               .is_some() {
-            acc
-        } else {
-            cx.expr_binary(item.span, BiAdd, acc,
-                           cx.expr_method_call(item.span,
-                                               item.self_.clone(),
-                                               substr.method_ident,
-                                               Vec::new()))
-                        }
-    })
-}
diff --git a/components/plugins/lib.rs b/components/plugins/lib.rs
index b1d701e6aec..25181f2197c 100644
--- a/components/plugins/lib.rs
+++ b/components/plugins/lib.rs
@@ -36,8 +36,6 @@ use syntax::parse::token::intern;
 // Public for documentation to show up
 /// Handles the auto-deriving for `#[derive(JSTraceable)]`
 pub mod jstraceable;
-/// Handles the auto-deriving for `#[derive(HeapSizeOf)]`
-pub mod heap_size;
 pub mod lints;
 /// Autogenerates implementations of Reflectable on DOM structs
 pub mod reflector;
@@ -51,7 +49,6 @@ pub fn plugin_registrar(reg: &mut Registry) {
     reg.register_syntax_extension(intern("dom_struct"), MultiModifier(box jstraceable::expand_dom_struct));
     reg.register_syntax_extension(intern("derive_JSTraceable"), MultiDecorator(box jstraceable::expand_jstraceable));
     reg.register_syntax_extension(intern("_generate_reflector"), MultiDecorator(box reflector::expand_reflector));
-    reg.register_syntax_extension(intern("derive_HeapSizeOf"), MultiDecorator(box heap_size::expand_heap_size));
     reg.register_macro("to_lower", casing::expand_lower);
     reg.register_macro("to_upper", casing::expand_upper);
     reg.register_macro("url", url_plugin::expand_url);
diff --git a/components/script/Cargo.toml b/components/script/Cargo.toml
index 67cfdedae6a..b06ae8e8e48 100644
--- a/components/script/Cargo.toml
+++ b/components/script/Cargo.toml
@@ -64,27 +64,29 @@ path = "../gfx_traits"
 
 [dependencies]
 app_units = {version = "0.2", features = ["plugins"]}
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
-log = "0.3"
+bitflags = "0.3"
+caseless = "0.1.0"
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
 encoding = "0.2"
+euclid = {version = "0.6.1", features = ["plugins"]}
 fnv = "1.0"
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
+html5ever = {version = "0.4.2", features = ["heap_size", "unstable"]}
 hyper = { version = "0.7", features = [ "serde-serialization" ] }
-time = "0.1.12"
-bitflags = "0.3"
-rustc-serialize = "0.3"
+image = "0.5.0"
 libc = "0.2"
-unicase = "1.0"
+log = "0.3"
 num = "0.1.24"
-websocket = "0.14.0"
-uuid = "0.1.16"
-smallvec = "0.1"
-html5ever = { version = "0.4", features = ["unstable"] }
-selectors = "0.4.1"
-string_cache = { version = "0.2", features = ["unstable"] }
-euclid = {version = "0.6.1", features = ["plugins"]}
 rand = "0.3"
-serde = "0.6"
-caseless = "0.1.0"
-image = "0.5.0"
-url = "0.5.4"
 ref_slice = "0.1.0"
+rustc-serialize = "0.3"
+selectors = {version = "0.4.1", features = ["heap_size"]}
+serde = "0.6"
+smallvec = "0.1"
+string_cache = {version = "0.2.7", features = ["heap_size", "unstable"]}
+time = "0.1.12"
+unicase = "1.0"
+url = {version = "0.5.4", features = ["heap_size"]}
+uuid = "0.1.16"
+websocket = "0.14.0"
diff --git a/components/script/cors.rs b/components/script/cors.rs
index 7bf5127a22e..e64583e0a58 100644
--- a/components/script/cors.rs
+++ b/components/script/cors.rs
@@ -27,7 +27,6 @@ use std::sync::{Arc, Mutex};
 use time::{self, Timespec, now};
 use unicase::UniCase;
 use url::{SchemeData, Url};
-use util::mem::HeapSizeOf;
 use util::thread::spawn_named;
 
 /// Interface for network listeners concerned with CORS checks. Proper network requests
@@ -41,6 +40,7 @@ pub struct CORSRequest {
     pub origin: Url,
     pub destination: Url,
     pub mode: RequestMode,
+    #[ignore_heap_size_of = "Defined in hyper"]
     pub method: Method,
     #[ignore_heap_size_of = "Defined in hyper"]
     pub headers: Headers,
diff --git a/components/script/dom/bindings/error.rs b/components/script/dom/bindings/error.rs
index 95f22e693e5..dafd14f58c9 100644
--- a/components/script/dom/bindings/error.rs
+++ b/components/script/dom/bindings/error.rs
@@ -14,7 +14,6 @@ use js::jsapi::{JSContext, JSObject, RootedValue};
 use js::jsapi::{JS_IsExceptionPending, JS_ReportPendingException, JS_SetPendingException};
 use js::jsapi::{JS_RestoreFrameChain, JS_SaveFrameChain};
 use js::jsval::UndefinedValue;
-use util::mem::HeapSizeOf;
 
 /// DOM exceptions that can be thrown by a native DOM method.
 #[derive(Debug, Clone, HeapSizeOf)]
diff --git a/components/script/dom/bindings/js.rs b/components/script/dom/bindings/js.rs
index 6abf5f9b4e5..37d673f3c26 100644
--- a/components/script/dom/bindings/js.rs
+++ b/components/script/dom/bindings/js.rs
@@ -30,6 +30,7 @@ use dom::bindings::reflector::{Reflectable, Reflector};
 use dom::bindings::trace::JSTraceable;
 use dom::bindings::trace::trace_reflector;
 use dom::node::Node;
+use heapsize::HeapSizeOf;
 use js::jsapi::{Heap, JSObject, JSTracer};
 use js::jsval::JSVal;
 use layout_interface::TrustedNodeAddress;
@@ -40,7 +41,6 @@ use std::hash::{Hash, Hasher};
 use std::mem;
 use std::ops::Deref;
 use std::ptr;
-use util::mem::HeapSizeOf;
 use util::thread_state;
 
 /// A traced reference to a DOM object
diff --git a/components/script/dom/bindings/str.rs b/components/script/dom/bindings/str.rs
index df69bc77fd0..26c8568eadf 100644
--- a/components/script/dom/bindings/str.rs
+++ b/components/script/dom/bindings/str.rs
@@ -10,7 +10,6 @@ use std::hash::{Hash, Hasher};
 use std::ops;
 use std::str;
 use std::str::FromStr;
-use util::mem::HeapSizeOf;
 use util::str::is_token;
 
 /// Encapsulates the IDL `ByteString` type.
diff --git a/components/script/dom/bindings/utils.rs b/components/script/dom/bindings/utils.rs
index d34d8f3f9f4..83e7a2e4cb2 100644
--- a/components/script/dom/bindings/utils.rs
+++ b/components/script/dom/bindings/utils.rs
@@ -13,6 +13,7 @@ use dom::bindings::inheritance::TopTypeId;
 use dom::bindings::trace::trace_object;
 use dom::browsingcontext;
 use dom::window;
+use heapsize::HeapSizeOf;
 use js;
 use js::error::throw_type_error;
 use js::glue::{CallJitGetterOp, CallJitMethodOp, CallJitSetterOp, IsWrapper};
@@ -36,7 +37,6 @@ use libc::{self, c_uint};
 use std::default::Default;
 use std::ffi::CString;
 use std::ptr;
-use util::mem::HeapSizeOf;
 use util::non_geckolib::jsstring_to_str;
 
 /// Proxy handler for a WindowProxy.
diff --git a/components/script/dom/bindings/weakref.rs b/components/script/dom/bindings/weakref.rs
index e311d4a40bb..99adb8a0c02 100644
--- a/components/script/dom/bindings/weakref.rs
+++ b/components/script/dom/bindings/weakref.rs
@@ -15,6 +15,7 @@ use core::nonzero::NonZero;
 use dom::bindings::js::Root;
 use dom::bindings::reflector::Reflectable;
 use dom::bindings::trace::JSTraceable;
+use heapsize::HeapSizeOf;
 use js::jsapi::{JSTracer, JS_GetReservedSlot, JS_SetReservedSlot};
 use js::jsval::PrivateValue;
 use libc::c_void;
@@ -22,7 +23,6 @@ use std::cell::{Cell, UnsafeCell};
 use std::iter::Iterator;
 use std::mem;
 use std::ops::{Deref, DerefMut, Drop};
-use util::mem::HeapSizeOf;
 
 /// The index of the slot wherein a pointer to the weak holder cell is
 /// stored for weak-referenceable bindings. We use slot 1 for holding it,
diff --git a/components/script/dom/crypto.rs b/components/script/dom/crypto.rs
index b8c595f3aa4..6e0351d37ee 100644
--- a/components/script/dom/crypto.rs
+++ b/components/script/dom/crypto.rs
@@ -20,6 +20,7 @@ no_jsmanaged_fields!(OsRng);
 #[dom_struct]
 pub struct Crypto {
     reflector_: Reflector,
+    #[ignore_heap_size_of = "Defined in rand"]
     rng: DOMRefCell<OsRng>,
 }
 
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index d093380b008..3cdf3f6ba43 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -84,7 +84,6 @@ use style::properties::{PropertyDeclaration, PropertyDeclarationBlock, parse_sty
 use style::selector_impl::{NonTSPseudoClass, ServoSelectorImpl};
 use style::values::CSSFloat;
 use style::values::specified::{self, CSSColor, CSSRGBA, LengthOrPercentage};
-use util::mem::HeapSizeOf;
 use util::str::{DOMString, LengthOrPercentageOrAuto};
 
 // TODO: Update focus state when the top-level browsing context gains or loses system focus,
diff --git a/components/script/dom/eventtarget.rs b/components/script/dom/eventtarget.rs
index 48682ec2211..2cf9517d606 100644
--- a/components/script/dom/eventtarget.rs
+++ b/components/script/dom/eventtarget.rs
@@ -21,6 +21,7 @@ use dom::eventdispatcher::dispatch_event;
 use dom::virtualmethods::VirtualMethods;
 use dom::window::Window;
 use fnv::FnvHasher;
+use heapsize::HeapSizeOf;
 use js::jsapi::{CompileFunction, JS_GetFunctionObject, RootedValue};
 use js::jsapi::{HandleObject, JSContext, RootedFunction};
 use js::jsapi::{JSAutoCompartment, JSAutoRequest};
@@ -35,7 +36,6 @@ use std::rc::Rc;
 use std::{intrinsics, ptr};
 use string_cache::Atom;
 use url::Url;
-use util::mem::HeapSizeOf;
 use util::str::DOMString;
 
 #[derive(PartialEq, Clone, JSTraceable)]
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 9c4e52b495d..a50aad1a78e 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -9,7 +9,6 @@ use core::nonzero::NonZero;
 use devtools_traits::NodeInfo;
 use document_loader::DocumentLoader;
 use dom::attr::Attr;
-use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::AttrBinding::AttrMethods;
 use dom::bindings::codegen::Bindings::CharacterDataBinding::CharacterDataMethods;
 use dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
@@ -47,6 +46,7 @@ use dom::text::Text;
 use dom::virtualmethods::{VirtualMethods, vtable_for};
 use dom::window::Window;
 use euclid::rect::Rect;
+use heapsize::{HeapSizeOf, heap_size_of};
 use js::jsapi::{JSContext, JSObject, JSRuntime};
 use layout_interface::{LayoutChan, Msg};
 use libc::{self, c_void, uintptr_t};
@@ -57,7 +57,7 @@ use selectors::matching::matches;
 use selectors::parser::Selector;
 use selectors::parser::parse_author_origin_selector_list_from_str;
 use std::borrow::ToOwned;
-use std::cell::Cell;
+use std::cell::{Cell, UnsafeCell};
 use std::cmp::max;
 use std::default::Default;
 use std::iter::{self, FilterMap, Peekable};
@@ -120,7 +120,7 @@ pub struct Node {
     /// node is finalized.
     style_and_layout_data: Cell<Option<OpaqueStyleAndLayoutData>>,
 
-    unique_id: DOMRefCell<Option<Box<Uuid>>>,
+    unique_id: UniqueId,
 }
 
 bitflags! {
@@ -755,11 +755,7 @@ impl Node {
     }
 
     pub fn get_unique_id(&self) -> String {
-        if self.unique_id.borrow().is_none() {
-            let mut unique_id = self.unique_id.borrow_mut();
-            *unique_id = Some(Box::new(Uuid::new_v4()));
-        }
-        self.unique_id.borrow().as_ref().unwrap().to_simple_string()
+        self.unique_id.borrow().to_simple_string()
     }
 
     pub fn summarize(&self) -> NodeInfo {
@@ -1266,7 +1262,7 @@ impl Node {
 
             style_and_layout_data: Cell::new(None),
 
-            unique_id: DOMRefCell::new(None),
+            unique_id: UniqueId::new(),
         }
     }
 
@@ -2438,3 +2434,40 @@ impl<'a> UnbindContext<'a> {
         index
     }
 }
+
+/// A node's unique ID, for devtools.
+struct UniqueId {
+    cell: UnsafeCell<Option<Box<Uuid>>>,
+}
+
+no_jsmanaged_fields!(UniqueId);
+
+impl HeapSizeOf for UniqueId {
+    #[allow(unsafe_code)]
+    fn heap_size_of_children(&self) -> usize {
+        if let &Some(ref uuid) = unsafe { &*self.cell.get() } {
+            heap_size_of(&** uuid as *const Uuid as *const c_void)
+        } else {
+            0
+        }
+    }
+}
+
+impl UniqueId {
+    /// Create a new `UniqueId` value. The underlying `Uuid` is lazily created.
+    fn new() -> UniqueId {
+        UniqueId { cell: UnsafeCell::new(None) }
+    }
+
+    /// The Uuid of that unique ID.
+    #[allow(unsafe_code)]
+    fn borrow(&self) -> &Uuid {
+        unsafe {
+            let ptr = self.cell.get();
+            if (*ptr).is_none() {
+                *ptr = Some(box Uuid::new_v4());
+            }
+            &(&*ptr).as_ref().unwrap()
+        }
+    }
+}
diff --git a/components/script/dom/range.rs b/components/script/dom/range.rs
index 03db51ba0d8..6807a7a2d3c 100644
--- a/components/script/dom/range.rs
+++ b/components/script/dom/range.rs
@@ -23,10 +23,10 @@ use dom::document::Document;
 use dom::documentfragment::DocumentFragment;
 use dom::node::{Node, UnbindContext};
 use dom::text::Text;
+use heapsize::HeapSizeOf;
 use js::jsapi::JSTracer;
 use std::cell::{Cell, UnsafeCell};
 use std::cmp::{Ord, Ordering, PartialEq, PartialOrd};
-use util::mem::HeapSizeOf;
 use util::str::DOMString;
 
 #[dom_struct]
diff --git a/components/script/dom/xmlhttprequest.rs b/components/script/dom/xmlhttprequest.rs
index e6b7374ef39..59feddfcc22 100644
--- a/components/script/dom/xmlhttprequest.rs
+++ b/components/script/dom/xmlhttprequest.rs
@@ -62,7 +62,6 @@ use string_cache::Atom;
 use time;
 use timers::{ScheduledCallback, TimerHandle};
 use url::Url;
-use util::mem::HeapSizeOf;
 use util::str::DOMString;
 
 pub type SendParam = BlobOrStringOrURLSearchParams;
@@ -127,11 +126,13 @@ pub struct XMLHttpRequest {
     response_xml: MutNullableHeap<JS<Document>>,
     #[ignore_heap_size_of = "Defined in hyper"]
     response_headers: DOMRefCell<Headers>,
+    #[ignore_heap_size_of = "Defined in hyper"]
     override_mime_type: DOMRefCell<Option<Mime>>,
     #[ignore_heap_size_of = "Defined in rust-encoding"]
     override_charset: DOMRefCell<Option<EncodingRef>>,
 
     // Associated concepts
+    #[ignore_heap_size_of = "Defined in hyper"]
     request_method: DOMRefCell<Method>,
     request_url: DOMRefCell<Option<Url>>,
     #[ignore_heap_size_of = "Defined in hyper"]
diff --git a/components/script/lib.rs b/components/script/lib.rs
index 6365c03c5b7..b857a00e122 100644
--- a/components/script/lib.rs
+++ b/components/script/lib.rs
@@ -26,6 +26,7 @@
 
 #![doc = "The script crate contains all matters DOM."]
 
+#![plugin(heapsize_plugin)]
 #![plugin(plugins)]
 
 extern crate angle;
@@ -42,6 +43,7 @@ extern crate encoding;
 extern crate euclid;
 extern crate fnv;
 extern crate gfx_traits;
+extern crate heapsize;
 extern crate html5ever;
 extern crate hyper;
 extern crate image;
diff --git a/components/script/mem.rs b/components/script/mem.rs
index 113f03b8396..e276b1a5c3d 100644
--- a/components/script/mem.rs
+++ b/components/script/mem.rs
@@ -6,8 +6,8 @@
 
 use dom::bindings::conversions::get_dom_class;
 use dom::bindings::reflector::Reflectable;
+use heapsize::{HeapSizeOf, heap_size_of};
 use libc::c_void;
-use util::mem::{HeapSizeOf, heap_size_of};
 
 // This is equivalent to measuring a Box<T>, except that DOM objects lose their
 // associated box in order to stash their pointers in a reserved slot of their
diff --git a/components/script/textinput.rs b/components/script/textinput.rs
index 5d533f0e419..02fb79e04a8 100644
--- a/components/script/textinput.rs
+++ b/components/script/textinput.rs
@@ -12,7 +12,6 @@ use std::borrow::ToOwned;
 use std::cmp::{max, min};
 use std::default::Default;
 use std::usize;
-use util::mem::HeapSizeOf;
 use util::str::DOMString;
 
 #[derive(Copy, Clone, PartialEq)]
diff --git a/components/script/timers.rs b/components/script/timers.rs
index 7f608f98f46..1c1157d30ae 100644
--- a/components/script/timers.rs
+++ b/components/script/timers.rs
@@ -9,6 +9,7 @@ use dom::bindings::reflector::Reflectable;
 use dom::bindings::trace::JSTraceable;
 use dom::window::ScriptHelpers;
 use euclid::length::Length;
+use heapsize::HeapSizeOf;
 use ipc_channel::ipc::IpcSender;
 use js::jsapi::{HandleValue, Heap, RootedValue};
 use js::jsval::{JSVal, UndefinedValue};
@@ -19,7 +20,6 @@ use std::cell::Cell;
 use std::cmp::{self, Ord, Ordering};
 use std::default::Default;
 use std::rc::Rc;
-use util::mem::HeapSizeOf;
 use util::str::DOMString;
 
 #[derive(JSTraceable, PartialEq, Eq, Copy, Clone, HeapSizeOf, Hash, PartialOrd, Ord, Debug)]
diff --git a/components/script_traits/Cargo.toml b/components/script_traits/Cargo.toml
index 5b3f25aa6fa..8644762b7db 100644
--- a/components/script_traits/Cargo.toml
+++ b/components/script_traits/Cargo.toml
@@ -42,9 +42,11 @@ git = "https://github.com/servo/ipc-channel"
 
 [dependencies]
 app_units = {version = "0.2", features = ["plugins"]}
-libc = "0.2"
 euclid = {version = "0.6.1", features = ["plugins"]}
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
+libc = "0.2"
 serde = "0.6"
 serde_macros = "0.6"
 time = "0.1.12"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index 9229c626ab6..83761f20090 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -7,7 +7,7 @@
 //! to depend on script.
 
 #![feature(custom_derive, plugin)]
-#![plugin(plugins, serde_macros)]
+#![plugin(heapsize_plugin, plugins, serde_macros)]
 #![deny(missing_docs)]
 
 extern crate app_units;
@@ -15,6 +15,7 @@ extern crate canvas_traits;
 extern crate devtools_traits;
 extern crate euclid;
 extern crate gfx_traits;
+extern crate heapsize;
 extern crate ipc_channel;
 extern crate libc;
 extern crate msg;
@@ -50,7 +51,6 @@ use profile_traits::mem;
 use std::any::Any;
 use url::Url;
 use util::ipc::OptionalOpaqueIpcSender;
-use util::mem::HeapSizeOf;
 
 pub use script_msg::{LayoutMsg, ScriptMsg};
 
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index 741c2982de1..f78d15b3b1b 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -80,7 +80,7 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -102,7 +102,7 @@ dependencies = [
  "core-text 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "freetype 0.1.0 (git+https://github.com/servo/rust-freetype)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -167,9 +167,11 @@ name = "canvas_traits"
 version = "0.0.1"
 dependencies = [
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
@@ -347,10 +349,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "cssparser"
-version = "0.5.0"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -391,6 +395,8 @@ name = "devtools_traits"
 version = "0.0.1"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "msg 0.0.1",
@@ -540,7 +546,7 @@ name = "euclid"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -647,6 +653,8 @@ dependencies = [
  "freetype 0.1.0 (git+https://github.com/servo/rust-freetype)",
  "gfx_traits 0.0.1",
  "harfbuzz-sys 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -665,7 +673,7 @@ dependencies = [
  "servo-skia 0.20130412.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "simd 0.1.0 (git+https://github.com/huonw/simd)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-script 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -688,6 +696,8 @@ version = "0.0.1"
 dependencies = [
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "msg 0.0.1",
  "plugins 0.0.1",
@@ -797,7 +807,7 @@ dependencies = [
 
 [[package]]
 name = "heapsize"
-version = "0.2.2"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -818,15 +828,17 @@ dependencies = [
 
 [[package]]
 name = "html5ever"
-version = "0.4.0"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "mac 0.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_codegen 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "tendril 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -918,7 +930,7 @@ name = "js"
 version = "0.1.1"
 source = "git+https://github.com/servo/rust-mozjs#b96675b217534c7742cbfda8150ea0536aedbdfb"
 dependencies = [
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "mozjs_sys 0.0.0 (git+https://github.com/servo/mozjs)",
@@ -956,7 +968,7 @@ dependencies = [
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "glx 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "io-surface 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -976,11 +988,13 @@ dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layout_traits 0.0.1",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -997,7 +1011,7 @@ dependencies = [
  "serde_json 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-bidi 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1167,8 +1181,10 @@ name = "msg"
 version = "0.0.1"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
@@ -1239,6 +1255,8 @@ dependencies = [
 name = "net_traits"
 version = "0.0.1"
 dependencies = [
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
@@ -1549,13 +1567,15 @@ dependencies = [
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
  "caseless 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "devtools_traits 0.0.1",
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
- "html5ever 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "html5ever 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
@@ -1575,7 +1595,7 @@ dependencies = [
  "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicase 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1604,6 +1624,8 @@ dependencies = [
  "devtools_traits 0.0.1",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
@@ -1625,12 +1647,14 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "quickersort 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1798,10 +1822,12 @@ dependencies = [
 
 [[package]]
 name = "string_cache"
-version = "0.2.5"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "debug_unreachable 0.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_generator 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_shared 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1814,10 +1840,12 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1828,7 +1856,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style_traits 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1840,12 +1868,12 @@ name = "style_tests"
 version = "0.0.1"
 dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
  "plugins 0.0.1",
  "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "style_traits 0.0.1",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1856,8 +1884,10 @@ dependencies = [
 name = "style_traits"
 version = "0.0.1"
 dependencies = [
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1972,6 +2002,8 @@ version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2004,10 +2036,12 @@ dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "html5ever 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "html5ever 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "js 0.1.1 (git+https://github.com/servo/rust-mozjs)",
@@ -2025,7 +2059,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "uuid 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -2209,7 +2243,7 @@ dependencies = [
  "phf 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_codegen 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "tendril 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
diff --git a/components/servo/Cargo.toml b/components/servo/Cargo.toml
index 7e4f3cc8151..1b0a92ff94e 100644
--- a/components/servo/Cargo.toml
+++ b/components/servo/Cargo.toml
@@ -163,8 +163,8 @@ version = "0.2"
 git = "https://github.com/ecoal95/rust-offscreen-rendering-context"
 
 [dependencies]
-env_logger = "0.3"
 bitflags = "0.3"
-libc = "0.2"
-url = {version = "0.5.4", features = ["serde_serialization", "query_encoding"]}
+env_logger = "0.3"
 euclid = {version = "0.6.1", features = ["plugins"]}
+libc = "0.2"
+url = {version = "0.5.4", features = ["heap_size", "serde_serialization", "query_encoding"]}
diff --git a/components/style/Cargo.toml b/components/style/Cargo.toml
index 60477f39602..85a300d17d6 100644
--- a/components/style/Cargo.toml
+++ b/components/style/Cargo.toml
@@ -20,21 +20,23 @@ path = "../style_traits"
 
 [dependencies]
 app_units = {version = "0.2", features = ["plugins"]}
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
 log = "0.3"
 encoding = "0.2"
 fnv = "1.0"
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 rustc-serialize = "0.3"
 matches = "0.1"
 bitflags = "0.3"
 num = "0.1.24"
 lazy_static = "0.1.10"
-selectors = { version = "0.4.1", features = ["unstable"] }
+selectors = {version = "0.4.1", features = ["heap_size", "unstable"]}
 smallvec = "0.1"
-string_cache = "0.2"
+string_cache = {version = "0.2.7", features = ["heap_size"]}
 euclid = {version = "0.6.1", features = ["plugins"]}
 serde = "0.6"
 serde_macros = "0.6"
 time = "0.1"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 
diff --git a/components/style/custom_properties.rs b/components/style/custom_properties.rs
index af9a2c4e7da..26fc794afb3 100644
--- a/components/style/custom_properties.rs
+++ b/components/style/custom_properties.rs
@@ -10,7 +10,6 @@ use std::collections::{HashMap, HashSet};
 use std::fmt;
 use std::sync::Arc;
 use string_cache::Atom;
-use util::mem::HeapSizeOf;
 
 // Does not include the `--` prefix
 pub type Name = Atom;
diff --git a/components/style/font_face.rs b/components/style/font_face.rs
index d42e0feb3e9..0810afac5a8 100644
--- a/components/style/font_face.rs
+++ b/components/style/font_face.rs
@@ -8,7 +8,6 @@ use parser::{ParserContext, log_css_error};
 use properties::longhands::font_family::parse_one_family;
 use std::ascii::AsciiExt;
 use url::Url;
-use util::mem::HeapSizeOf;
 
 #[derive(Clone, Debug, HeapSizeOf, PartialEq, Eq, Deserialize, Serialize)]
 pub enum Source {
diff --git a/components/style/lib.rs b/components/style/lib.rs
index dee1d51efc6..6dbb7250ffc 100644
--- a/components/style/lib.rs
+++ b/components/style/lib.rs
@@ -11,9 +11,9 @@
 #![feature(custom_derive)]
 #![feature(plugin)]
 
-#![plugin(serde_macros)]
-#![plugin(serde_macros)]
+#![plugin(heapsize_plugin)]
 #![plugin(plugins)]
+#![plugin(serde_macros)]
 
 #![recursion_limit = "500"]  // For match_ignore_ascii_case in PropertyDeclaration::parse
 
@@ -26,6 +26,7 @@ extern crate cssparser;
 extern crate encoding;
 extern crate euclid;
 extern crate fnv;
+extern crate heapsize;
 #[macro_use]
 extern crate lazy_static;
 #[macro_use]
diff --git a/components/style/media_queries.rs b/components/style/media_queries.rs
index 82b02cc9701..b19b4d81c7e 100644
--- a/components/style/media_queries.rs
+++ b/components/style/media_queries.rs
@@ -8,7 +8,6 @@ use euclid::size::{Size2D, TypedSize2D};
 use properties::longhands;
 use std::ascii::AsciiExt;
 use util::geometry::ViewportPx;
-use util::mem::HeapSizeOf;
 use values::specified;
 
 
diff --git a/components/style/stylesheets.rs b/components/style/stylesheets.rs
index ce21cf68522..bc4008040c2 100644
--- a/components/style/stylesheets.rs
+++ b/components/style/stylesheets.rs
@@ -19,7 +19,6 @@ use std::iter::Iterator;
 use std::slice;
 use string_cache::{Atom, Namespace};
 use url::Url;
-use util::mem::HeapSizeOf;
 use viewport::ViewportRule;
 
 
diff --git a/components/style/viewport.rs b/components/style/viewport.rs
index e46d22c19b1..f50a2a5fb2b 100644
--- a/components/style/viewport.rs
+++ b/components/style/viewport.rs
@@ -18,7 +18,6 @@ use std::str::Chars;
 use style_traits::viewport::{Orientation, UserZoom, ViewportConstraints, Zoom};
 use stylesheets::Origin;
 use util::geometry::ViewportPx;
-use util::mem::HeapSizeOf;
 use values::computed::{Context, ToComputedValue};
 use values::specified::{Length, LengthOrPercentageOrAuto, ViewportPercentageLength};
 
diff --git a/components/style_traits/Cargo.toml b/components/style_traits/Cargo.toml
index 302ac6d8076..4d4ce440488 100644
--- a/components/style_traits/Cargo.toml
+++ b/components/style_traits/Cargo.toml
@@ -14,14 +14,15 @@ path = "../util"
 path = "../plugins"
 
 [dependencies]
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
 euclid = {version = "0.6.1", features = ["plugins"]}
-log = "0.3"
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
 lazy_static = "0.1.10"
+log = "0.3"
 num = "0.1.24"
 rustc-serialize = "0.3"
-selectors = "0.4.1"
+selectors = {version = "0.4.1", features = ["heap_size"]}
 serde = "0.6"
 serde_macros = "0.6"
-url = "0.5.4"
-
+url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/components/style_traits/lib.rs b/components/style_traits/lib.rs
index 5a56874514d..9e65308207e 100644
--- a/components/style_traits/lib.rs
+++ b/components/style_traits/lib.rs
@@ -10,6 +10,7 @@
 #![crate_type = "rlib"]
 #![feature(custom_derive)]
 #![feature(plugin)]
+#![plugin(heapsize_plugin)]
 #![plugin(serde_macros)]
 #![plugin(plugins)]
 #![deny(unsafe_code)]
@@ -17,6 +18,7 @@
 #[macro_use]
 extern crate cssparser;
 extern crate euclid;
+extern crate heapsize;
 extern crate rustc_serialize;
 extern crate serde;
 extern crate util;
diff --git a/components/util/Cargo.toml b/components/util/Cargo.toml
index 78a12b029ef..6d5ef0714a8 100644
--- a/components/util/Cargo.toml
+++ b/components/util/Cargo.toml
@@ -46,25 +46,27 @@ git = "https://github.com/servo/ipc-channel"
 
 [dependencies]
 app_units = {version = "0.2", features = ["plugins"]}
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
-log = "0.3"
 bitflags = "0.3"
-html5ever = { version = "0.4", features = ["unstable"], optional = true }
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
+euclid = {version = "0.6.1", features = ["unstable", "plugins"]}
+getopts = "0.2.11"
+html5ever = {version = "0.4.2", features = ["heap_size", "unstable"], optional = true}
+heapsize = "0.2.5"
+heapsize_plugin = "0.1.2"
+hyper = { version = "0.7", optional = true }
+lazy_static = "0.1"
 libc = "0.2"
+log = "0.3"
+num = "0.1.24"
+num_cpus = "0.2.2"
 rand = "0.3"
 rustc-serialize = "0.3"
-smallvec = "0.1"
-num_cpus = "0.2.2"
-num = "0.1.24"
-euclid = {version = "0.6.1", features = ["unstable", "plugins"]}
-selectors = "0.4.1"
+selectors = {version = "0.4.1", features = ["heap_size"]}
 serde = "0.6"
 serde_macros = "0.6"
-string_cache = "0.2"
-lazy_static = "0.1"
-getopts = "0.2.11"
-hyper = { version = "0.7", optional = true }
-url = {version = "0.5.4", features = ["serde_serialization"]}
+smallvec = "0.1"
+string_cache = {version = "0.2.7", features = ["heap_size"]}
+url = {version = "0.5.4", features = ["heap_size", "serde_serialization"]}
 uuid = "0.1.17"
 
 [target.x86_64-pc-windows-gnu.dependencies]
diff --git a/components/util/cursor.rs b/components/util/cursor.rs
index fa7ceb413c6..7f139fd498e 100644
--- a/components/util/cursor.rs
+++ b/components/util/cursor.rs
@@ -9,7 +9,7 @@ use std::ascii::AsciiExt;
 
 macro_rules! define_cursor {
     ($( $css: expr => $variant: ident = $value: expr, )+) => {
-        #[derive(Clone, Copy, PartialEq, Eq, Debug, Deserialize, Serialize)]
+        #[derive(Clone, Copy, Debug, Deserialize, Eq, HeapSizeOf, PartialEq, Serialize)]
         #[repr(u8)]
         pub enum Cursor {
             $( $variant = $value ),+
diff --git a/components/util/geometry.rs b/components/util/geometry.rs
index 4af85d703c9..813cad3aa3d 100644
--- a/components/util/geometry.rs
+++ b/components/util/geometry.rs
@@ -23,7 +23,7 @@ use std::i32;
 ///
 /// The ratio between ScreenPx and DevicePixel for a given display be found by calling
 /// `servo::windowing::WindowMethods::hidpi_factor`.
-#[derive(Debug, Copy, Clone)]
+#[derive(Clone, Copy, Debug, HeapSizeOf)]
 pub enum ScreenPx {}
 
 /// One CSS "px" in the coordinate system of the "initial viewport":
@@ -35,7 +35,7 @@ pub enum ScreenPx {}
 ///
 /// At the default zoom level of 100%, one PagePx is equal to one ScreenPx.  However, if the
 /// document is zoomed in or out then this scale may be larger or smaller.
-#[derive(RustcEncodable, Debug, Copy, Clone)]
+#[derive(Clone, Copy, Debug, HeapSizeOf)]
 pub enum ViewportPx {}
 
 /// One CSS "px" in the root coordinate system for the content document.
@@ -44,7 +44,7 @@ pub enum ViewportPx {}
 /// This is the mobile-style "pinch zoom" that enlarges content without reflowing it.  When the
 /// viewport zoom is not equal to 1.0, then the layout viewport is no longer the same physical size
 /// as the viewable area.
-#[derive(RustcEncodable, Debug, Copy, Clone)]
+#[derive(Clone, Copy, Debug, HeapSizeOf)]
 pub enum PagePx {}
 
 // In summary, the hierarchy of pixel units and the factors to convert from one to the next:
diff --git a/components/util/lib.rs b/components/util/lib.rs
index 660945d4c1a..61d99cb5a02 100644
--- a/components/util/lib.rs
+++ b/components/util/lib.rs
@@ -18,7 +18,7 @@
 #![feature(step_trait)]
 #![feature(zero_one)]
 
-#![plugin(plugins, serde_macros)]
+#![plugin(heapsize_plugin, plugins, serde_macros)]
 
 extern crate alloc;
 extern crate app_units;
@@ -30,6 +30,7 @@ extern crate bitflags;
 extern crate cssparser;
 extern crate euclid;
 extern crate getopts;
+extern crate heapsize;
 #[cfg(feature = "non-geckolib")]
 extern crate html5ever;
 #[cfg(feature = "non-geckolib")]
@@ -66,7 +67,6 @@ pub mod geometry;
 pub mod ipc;
 pub mod linked_list;
 pub mod logical_geometry;
-#[macro_use] pub mod mem;
 #[cfg(feature = "non-geckolib")]
 pub mod non_geckolib;
 pub mod opts;
diff --git a/components/util/logical_geometry.rs b/components/util/logical_geometry.rs
index 0c4372ce7f2..661ef0c6a65 100644
--- a/components/util/logical_geometry.rs
+++ b/components/util/logical_geometry.rs
@@ -11,7 +11,7 @@ use std::fmt::{self, Debug, Error, Formatter};
 use std::ops::{Add, Sub};
 
 bitflags!(
-    #[derive(RustcEncodable)]
+    #[derive(HeapSizeOf, RustcEncodable)]
     flags WritingMode: u8 {
         const FLAG_RTL = 1 << 0,
         const FLAG_VERTICAL = 1 << 1,
diff --git a/components/util/mem.rs b/components/util/mem.rs
deleted file mode 100644
index b5654b24123..00000000000
--- a/components/util/mem.rs
+++ /dev/null
@@ -1,360 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-//! Data structure measurement.
-
-use app_units::Au;
-use cssparser::Color as CSSParserColor;
-use cssparser::{RGBA, TokenSerializationType};
-use cursor::Cursor;
-use euclid::length::Length;
-use euclid::scale_factor::ScaleFactor;
-use euclid::{Matrix2D, Matrix4, Point2D, Rect, SideOffsets2D, Size2D};
-use geometry::{PagePx, ViewportPx};
-use libc::{c_void, size_t};
-use logical_geometry::WritingMode;
-use rand::OsRng;
-use range::Range;
-use selectors::parser::{Combinator, CompoundSelector, Selector, SimpleSelector, SelectorImpl};
-use std::cell::{Cell, RefCell};
-use std::collections::{HashMap, LinkedList};
-use std::hash::{BuildHasher, Hash};
-use std::mem::{size_of, transmute};
-use std::rc::Rc;
-use std::result::Result;
-use std::sync::Arc;
-use std::sync::atomic::{AtomicIsize, AtomicUsize};
-use str::{DOMString, LengthOrPercentageOrAuto};
-use string_cache::atom::Atom;
-use string_cache::namespace::{QualName, Namespace};
-use url;
-use uuid::Uuid;
-
-extern {
-    // Get the size of a heap block.
-    //
-    // Ideally Rust would expose a function like this in std::rt::heap, which would avoid the
-    // jemalloc dependence.
-    //
-    // The C prototype is `je_malloc_usable_size(JEMALLOC_USABLE_SIZE_CONST void *ptr)`. On some
-    // platforms `JEMALLOC_USABLE_SIZE_CONST` is `const` and on some it is empty. But in practice
-    // this function doesn't modify the contents of the block that `ptr` points to, so we use
-    // `*const c_void` here.
-    fn je_malloc_usable_size(ptr: *const c_void) -> size_t;
-}
-
-// A wrapper for je_malloc_usable_size that handles `EMPTY` and returns `usize`.
-pub fn heap_size_of(ptr: *const c_void) -> usize {
-    if ptr == ::alloc::heap::EMPTY as *const c_void {
-        0
-    } else {
-        unsafe { je_malloc_usable_size(ptr) as usize }
-    }
-}
-
-// The simplest trait for measuring the size of heap data structures. More complex traits that
-// return multiple measurements -- e.g. measure text separately from images -- are also possible,
-// and should be used when appropriate.
-//
-pub trait HeapSizeOf {
-    /// Measure the size of any heap-allocated structures that hang off this value, but not the
-    /// space taken up by the value itself (i.e. what size_of::<T> measures, more or less); that
-    /// space is handled by the implementation of HeapSizeOf for Box<T> below.
-    fn heap_size_of_children(&self) -> usize;
-}
-
-// There are two possible ways to measure the size of `self` when it's on the heap: compute it
-// (with `::std::rt::heap::usable_size(::std::mem::size_of::<T>(), 0)`) or measure it directly
-// using the heap allocator (with `heap_size_of`). We do the latter, for the following reasons.
-//
-// * The heap allocator is the true authority for the sizes of heap blocks; its measurement is
-//   guaranteed to be correct. In comparison, size computations are error-prone. (For example, the
-//   `rt::heap::usable_size` function used in some of Rust's non-default allocator implementations
-//   underestimate the true usable size of heap blocks, which is safe in general but would cause
-//   under-measurement here.)
-//
-// * If we measure something that isn't a heap block, we'll get a crash. This keeps us honest,
-//   which is important because unsafe code is involved and this can be gotten wrong.
-//
-// However, in the best case, the two approaches should give the same results.
-//
-impl<T: HeapSizeOf> HeapSizeOf for Box<T> {
-    fn heap_size_of_children(&self) -> usize {
-        // Measure size of `self`.
-        heap_size_of(&**self as *const T as *const c_void) + (**self).heap_size_of_children()
-    }
-}
-
-impl HeapSizeOf for String {
-    fn heap_size_of_children(&self) -> usize {
-        heap_size_of(self.as_ptr() as *const c_void)
-    }
-}
-
-impl HeapSizeOf for DOMString {
-    fn heap_size_of_children(&self) -> usize {
-        heap_size_of(self.as_ptr() as *const c_void)
-    }
-}
-
-impl<T: HeapSizeOf> HeapSizeOf for Option<T> {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            None => 0,
-            Some(ref x) => x.heap_size_of_children()
-        }
-    }
-}
-
-impl HeapSizeOf for url::Url {
-    fn heap_size_of_children(&self) -> usize {
-        // Using a struct pattern without `..` rather than `foo.bar` field access
-        // makes sure this will be updated if a field is added.
-        let &url::Url { ref scheme, ref scheme_data, ref query, ref fragment } = self;
-        scheme.heap_size_of_children() +
-        scheme_data.heap_size_of_children() +
-        query.heap_size_of_children() +
-        fragment.heap_size_of_children()
-    }
-}
-
-impl HeapSizeOf for url::SchemeData {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            url::SchemeData::Relative(ref data) => data.heap_size_of_children(),
-            url::SchemeData::NonRelative(ref str) => str.heap_size_of_children()
-        }
-    }
-}
-
-impl HeapSizeOf for url::RelativeSchemeData {
-    fn heap_size_of_children(&self) -> usize {
-        // Using a struct pattern without `..` rather than `foo.bar` field access
-        // makes sure this will be updated if a field is added.
-        let &url::RelativeSchemeData { ref username, ref password, ref host,
-                                       ref port, ref default_port, ref path } = self;
-        username.heap_size_of_children() +
-        password.heap_size_of_children() +
-        host.heap_size_of_children() +
-        port.heap_size_of_children() +
-        default_port.heap_size_of_children() +
-        path.heap_size_of_children()
-    }
-}
-
-impl HeapSizeOf for url::Host {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            url::Host::Domain(ref str) => str.heap_size_of_children(),
-            url::Host::Ipv6(_) => 0,
-            url::Host::Ipv4(_) => 0,
-        }
-    }
-}
-
-impl<T: HeapSizeOf, U: HeapSizeOf> HeapSizeOf for (T, U) {
-    fn heap_size_of_children(&self) -> usize {
-        self.0.heap_size_of_children() + self.1.heap_size_of_children()
-    }
-}
-
-impl<T: HeapSizeOf> HeapSizeOf for Arc<T> {
-    fn heap_size_of_children(&self) -> usize {
-        (**self).heap_size_of_children()
-    }
-}
-
-impl<T: HeapSizeOf> HeapSizeOf for RefCell<T> {
-    fn heap_size_of_children(&self) -> usize {
-        self.borrow().heap_size_of_children()
-    }
-}
-
-impl<T: HeapSizeOf + Copy> HeapSizeOf for Cell<T> {
-    fn heap_size_of_children(&self) -> usize {
-        self.get().heap_size_of_children()
-    }
-}
-
-impl<T: HeapSizeOf> HeapSizeOf for Vec<T> {
-    fn heap_size_of_children(&self) -> usize {
-        heap_size_of(self.as_ptr() as *const c_void) +
-            self.iter().fold(0, |n, elem| n + elem.heap_size_of_children())
-    }
-}
-
-impl<T> HeapSizeOf for Vec<Rc<T>> {
-    fn heap_size_of_children(&self) -> usize {
-        // The fate of measuring Rc<T> is still undecided, but we still want to measure
-        // the space used for storing them.
-        heap_size_of(self.as_ptr() as *const c_void)
-    }
-}
-
-impl<K: HeapSizeOf, V: HeapSizeOf, S> HeapSizeOf for HashMap<K, V, S>
-    where K: Eq + Hash, S: BuildHasher {
-    fn heap_size_of_children(&self) -> usize {
-        //TODO(#6908) measure actual bucket memory usage instead of approximating
-        let size = self.capacity() * (size_of::<V>() + size_of::<K>());
-        self.iter().fold(size, |n, (key, value)| {
-            n + key.heap_size_of_children() + value.heap_size_of_children()
-        })
-    }
-}
-
-// FIXME(njn): We can't implement HeapSizeOf accurately for LinkedList because it requires access
-// to the private Node type. Eventually we'll want to add HeapSizeOf (or equivalent) to Rust
-// itself. In the meantime, we use the dirty hack of transmuting LinkedList into an identical type
-// (LinkedList2) and measuring that.
-impl<T: HeapSizeOf> HeapSizeOf for LinkedList<T> {
-    fn heap_size_of_children(&self) -> usize {
-        let list2: &LinkedList2<T> = unsafe { transmute(self) };
-        list2.heap_size_of_children()
-    }
-}
-
-struct LinkedList2<T> {
-    _length: usize,
-    list_head: Link<T>,
-    _list_tail: Rawlink<Node<T>>,
-}
-
-type Link<T> = Option<Box<Node<T>>>;
-
-struct Rawlink<T> {
-    _p: *mut T,
-}
-
-struct Node<T> {
-    next: Link<T>,
-    _prev: Rawlink<Node<T>>,
-    value: T,
-}
-
-impl<T: HeapSizeOf> HeapSizeOf for Node<T> {
-    // Unlike most heap_size_of_children() functions, this one does *not* measure descendents.
-    // Instead, LinkedList2<T>::heap_size_of_children() handles that, so that it can use iteration
-    // instead of recursion, which avoids potentially blowing the stack.
-    fn heap_size_of_children(&self) -> usize {
-        self.value.heap_size_of_children()
-    }
-}
-
-impl<T: HeapSizeOf> HeapSizeOf for LinkedList2<T> {
-    fn heap_size_of_children(&self) -> usize {
-        let mut size = 0;
-        let mut curr: &Link<T> = &self.list_head;
-        while curr.is_some() {
-            size += (*curr).heap_size_of_children();
-            curr = &curr.as_ref().unwrap().next;
-        }
-        size
-    }
-}
-
-// This is a basic sanity check. If the representation of LinkedList changes such that it becomes a
-// different size to LinkedList2, this will fail at compile-time.
-#[allow(dead_code)]
-unsafe fn linked_list2_check() {
-    transmute::<LinkedList<i32>, LinkedList2<i32>>(panic!());
-}
-
-// Currently, types that implement the Drop type are larger than those that don't. Because
-// LinkedList implements Drop, LinkedList2 must also so that linked_list2_check() doesn't fail.
-impl<T> Drop for LinkedList2<T> {
-    fn drop(&mut self) {}
-}
-
-/// For use on types defined in external crates
-/// with known heap sizes.
-#[macro_export]
-macro_rules! known_heap_size(
-    ($size:expr, $($ty:ident),+) => (
-        $(
-            impl $crate::mem::HeapSizeOf for $ty {
-                #[inline(always)]
-                fn heap_size_of_children(&self) -> usize {
-                    $size
-                }
-            }
-        )+
-    );
-    ($size: expr, $($ty:ident<$($gen:ident),+>),+) => (
-        $(
-        impl<$($gen: $crate::mem::HeapSizeOf),+> $crate::mem::HeapSizeOf for $ty<$($gen),+> {
-            #[inline(always)]
-            fn heap_size_of_children(&self) -> usize {
-                $size
-            }
-        }
-        )+
-    );
-);
-
-impl<T: HeapSizeOf, U: HeapSizeOf> HeapSizeOf for Result<T, U> {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            Result::Ok(ref ok) => ok.heap_size_of_children(),
-            Result::Err(ref err) => err.heap_size_of_children()
-        }
-    }
-}
-
-impl HeapSizeOf for () {
-    fn heap_size_of_children(&self) -> usize {
-        0
-    }
-}
-
-impl<T: SelectorImpl> HeapSizeOf for Selector<T>
-    where T::NonTSPseudoClass: HeapSizeOf,
-          T::PseudoElement: HeapSizeOf {
-    fn heap_size_of_children(&self) -> usize {
-        let &Selector { ref compound_selectors, ref pseudo_element, ref specificity } = self;
-        compound_selectors.heap_size_of_children() + pseudo_element.heap_size_of_children() +
-        specificity.heap_size_of_children()
-    }
-}
-
-impl<T: SelectorImpl> HeapSizeOf for CompoundSelector<T>
-    where T::NonTSPseudoClass: HeapSizeOf {
-    fn heap_size_of_children(&self) -> usize {
-        let &CompoundSelector { ref simple_selectors, ref next } = self;
-        simple_selectors.heap_size_of_children() + next.heap_size_of_children()
-    }
-}
-
-impl<T: SelectorImpl> HeapSizeOf for SimpleSelector<T>
-    where T::NonTSPseudoClass: HeapSizeOf {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            SimpleSelector::Negation(ref vec) => vec.heap_size_of_children(),
-            SimpleSelector::AttrIncludes(_, ref str) | SimpleSelector::AttrPrefixMatch(_, ref str) |
-            SimpleSelector::AttrSubstringMatch(_, ref str) | SimpleSelector::AttrSuffixMatch(_, ref str)
-                => str.heap_size_of_children(),
-            SimpleSelector::AttrEqual(_, ref str, _) => str.heap_size_of_children(),
-            SimpleSelector::AttrDashMatch(_, ref first, ref second)
-                => first.heap_size_of_children() + second.heap_size_of_children(),
-            SimpleSelector::NonTSPseudoClass(ref pseudo_class)
-                => pseudo_class.heap_size_of_children(),
-            // All other types come down to Atom, enum or i32, all 0
-            _ => 0
-        }
-    }
-}
-
-known_heap_size!(0, u8, u16, u32, u64, usize);
-known_heap_size!(0, i8, i16, i32, i64, isize);
-known_heap_size!(0, bool, f32, f64);
-known_heap_size!(0, AtomicIsize, AtomicUsize);
-
-known_heap_size!(0, Rect<T>, Point2D<T>, Size2D<T>, Matrix2D<T>, SideOffsets2D<T>, Range<T>);
-known_heap_size!(0, Length<T, U>, ScaleFactor<T, U, V>);
-
-known_heap_size!(0, Au, WritingMode, CSSParserColor, RGBA, Cursor, Matrix4, QualName, Atom, Namespace);
-known_heap_size!(0, PagePx, ViewportPx, OsRng);
-known_heap_size!(0, TokenSerializationType, LengthOrPercentageOrAuto);
-
-known_heap_size!(0, Combinator, str);
-known_heap_size!(0, Uuid);
diff --git a/components/util/non_geckolib.rs b/components/util/non_geckolib.rs
index cb047a0ec18..ff09ca5c983 100644
--- a/components/util/non_geckolib.rs
+++ b/components/util/non_geckolib.rs
@@ -4,20 +4,10 @@
 
 ///! Miscellaneous Code which depends on large libraries that we don't
 ///  depend on in GeckoLib builds.
-
-use azure::azure_hl::Color;
-use html5ever::tree_builder::QuirksMode;
-use hyper::header::ContentType;
-use hyper::http::RawStatus;
-use hyper::method::Method;
-use hyper::mime::{Attr, Mime, SubLevel, TopLevel, Value};
 use js::conversions::{FromJSValConvertible, ToJSValConvertible, latin1_to_string};
-use js::jsapi::{JSContext, JSString, HandleValue, Heap, MutableHandleValue};
+use js::jsapi::{JSContext, JSString, HandleValue, MutableHandleValue};
 use js::jsapi::{JS_GetTwoByteStringCharsAndLength, JS_StringHasLatin1Chars};
-use js::jsval::JSVal;
-use js::rust::{GCMethods, ToString};
-use layers::geometry::DevicePixel;
-use mem::HeapSizeOf;
+use js::rust::ToString;
 use opts;
 use std::char;
 use std::ptr;
@@ -99,73 +89,3 @@ pub unsafe fn jsstring_to_str(cx: *mut JSContext, s: *mut JSString) -> DOMString
         s
     })
 }
-
-// This is measured properly by the heap measurement implemented in SpiderMonkey.
-impl<T: Copy + GCMethods<T>> HeapSizeOf for Heap<T> {
-    fn heap_size_of_children(&self) -> usize {
-        0
-    }
-}
-
-impl HeapSizeOf for ContentType {
-    fn heap_size_of_children(&self) -> usize {
-        let &ContentType(ref mime) = self;
-        mime.heap_size_of_children()
-    }
-}
-
-impl HeapSizeOf for Method {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            Method::Extension(ref str) => str.heap_size_of_children(),
-            _ => 0
-        }
-    }
-}
-
-impl HeapSizeOf for Mime {
-    fn heap_size_of_children(&self) -> usize {
-        let &Mime(ref top_level, ref sub_level, ref vec) = self;
-        top_level.heap_size_of_children() + sub_level.heap_size_of_children() +
-        vec.heap_size_of_children()
-    }
-}
-
-impl HeapSizeOf for TopLevel {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            TopLevel::Ext(ref str) => str.heap_size_of_children(),
-            _ => 0
-        }
-    }
-}
-
-impl HeapSizeOf for SubLevel {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            SubLevel::Ext(ref str) => str.heap_size_of_children(),
-            _ => 0
-        }
-    }
-}
-
-impl HeapSizeOf for Attr {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            Attr::Ext(ref str) => str.heap_size_of_children(),
-            _ => 0
-        }
-    }
-}
-
-impl HeapSizeOf for Value {
-    fn heap_size_of_children(&self) -> usize {
-        match *self {
-            Value::Ext(ref str) => str.heap_size_of_children(),
-            _ => 0
-        }
-    }
-}
-
-
-known_heap_size!(0, Color, DevicePixel, JSVal, QuirksMode, RawStatus);
diff --git a/components/util/range.rs b/components/util/range.rs
index 07e66b28a6f..8149a1f424c 100644
--- a/components/util/range.rs
+++ b/components/util/range.rs
@@ -136,7 +136,7 @@ macro_rules! int_range_index {
 }
 
 /// A range of indices
-#[derive(Clone, RustcEncodable, Copy, Deserialize, Serialize)]
+#[derive(Clone, Copy, Deserialize, HeapSizeOf, RustcEncodable, Serialize)]
 pub struct Range<I> {
     begin: I,
     length: I,
diff --git a/components/util/str.rs b/components/util/str.rs
index dc3b8df1762..8ffcf67b0e9 100644
--- a/components/util/str.rs
+++ b/components/util/str.rs
@@ -16,7 +16,7 @@ use std::iter::{Filter, Peekable};
 use std::ops::{Deref, DerefMut};
 use std::str::{Bytes, CharIndices, FromStr, Split, from_utf8};
 
-#[derive(Clone, PartialOrd, Ord, PartialEq, Eq, Deserialize, Serialize, Hash, Debug)]
+#[derive(Clone, Debug, Deserialize, Eq, Hash, HeapSizeOf, Ord, PartialEq, PartialOrd, Serialize)]
 pub struct DOMString(String);
 
 impl !Send for DOMString {}
@@ -220,7 +220,7 @@ pub fn parse_unsigned_integer<T: Iterator<Item=char>>(input: T) -> Option<u32> {
     })
 }
 
-#[derive(Copy, Clone, Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, HeapSizeOf, PartialEq)]
 pub enum LengthOrPercentageOrAuto {
     Auto,
     Percentage(f32),
diff --git a/components/webdriver_server/Cargo.toml b/components/webdriver_server/Cargo.toml
index d489479bc61..20e4ff5c7a4 100644
--- a/components/webdriver_server/Cargo.toml
+++ b/components/webdriver_server/Cargo.toml
@@ -31,5 +31,5 @@ log = "0.3"
 hyper = "0.7"
 rustc-serialize = "0.3.4"
 regex = "0.1.33"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 uuid = "0.1"
diff --git a/ports/cef/Cargo.lock b/ports/cef/Cargo.lock
index db38b7e7a2c..796fcb6d639 100644
--- a/ports/cef/Cargo.lock
+++ b/ports/cef/Cargo.lock
@@ -68,7 +68,7 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -90,7 +90,7 @@ dependencies = [
  "core-text 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "freetype 0.1.0 (git+https://github.com/servo/rust-freetype)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -155,9 +155,11 @@ name = "canvas_traits"
 version = "0.0.1"
 dependencies = [
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
@@ -320,10 +322,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "cssparser"
-version = "0.5.0"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -364,6 +368,8 @@ name = "devtools_traits"
 version = "0.0.1"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "msg 0.0.1",
@@ -480,7 +486,7 @@ name = "euclid"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -587,6 +593,8 @@ dependencies = [
  "freetype 0.1.0 (git+https://github.com/servo/rust-freetype)",
  "gfx_traits 0.0.1",
  "harfbuzz-sys 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -605,7 +613,7 @@ dependencies = [
  "servo-skia 0.20130412.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "simd 0.1.0 (git+https://github.com/huonw/simd)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-script 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -619,6 +627,8 @@ version = "0.0.1"
 dependencies = [
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "msg 0.0.1",
  "plugins 0.0.1",
@@ -728,7 +738,7 @@ dependencies = [
 
 [[package]]
 name = "heapsize"
-version = "0.2.2"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -749,15 +759,17 @@ dependencies = [
 
 [[package]]
 name = "html5ever"
-version = "0.4.0"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "mac 0.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_codegen 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "tendril 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -849,7 +861,7 @@ name = "js"
 version = "0.1.1"
 source = "git+https://github.com/servo/rust-mozjs#b96675b217534c7742cbfda8150ea0536aedbdfb"
 dependencies = [
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "mozjs_sys 0.0.0 (git+https://github.com/servo/mozjs)",
@@ -887,7 +899,7 @@ dependencies = [
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "glx 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "io-surface 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -907,11 +919,13 @@ dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layout_traits 0.0.1",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -928,7 +942,7 @@ dependencies = [
  "serde_json 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-bidi 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1098,8 +1112,10 @@ name = "msg"
 version = "0.0.1"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
@@ -1152,6 +1168,8 @@ dependencies = [
 name = "net_traits"
 version = "0.0.1"
 dependencies = [
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
@@ -1437,13 +1455,15 @@ dependencies = [
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
  "caseless 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "devtools_traits 0.0.1",
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
- "html5ever 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "html5ever 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
@@ -1463,7 +1483,7 @@ dependencies = [
  "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicase 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1483,6 +1503,8 @@ dependencies = [
  "devtools_traits 0.0.1",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
@@ -1504,12 +1526,14 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "quickersort 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1712,10 +1736,12 @@ dependencies = [
 
 [[package]]
 name = "string_cache"
-version = "0.2.5"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "debug_unreachable 0.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_generator 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_shared 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1728,10 +1754,12 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1742,7 +1770,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style_traits 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1753,8 +1781,10 @@ dependencies = [
 name = "style_traits"
 version = "0.0.1"
 dependencies = [
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1869,6 +1899,8 @@ version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1901,10 +1933,12 @@ dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "html5ever 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "html5ever 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "js 0.1.1 (git+https://github.com/servo/rust-mozjs)",
@@ -1922,7 +1956,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "uuid 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -2095,7 +2129,7 @@ dependencies = [
  "phf 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_codegen 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "tendril 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
diff --git a/ports/cef/Cargo.toml b/ports/cef/Cargo.toml
index b03fce61e53..a47bfe10e21 100644
--- a/ports/cef/Cargo.toml
+++ b/ports/cef/Cargo.toml
@@ -14,7 +14,7 @@ gleam = "0.2"
 libc = "0.2"
 log = "0.3"
 stb_image = "0.2"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 
 [dependencies.servo]
 path = "../../components/servo"
diff --git a/ports/geckolib/Cargo.lock b/ports/geckolib/Cargo.lock
index 199881d2538..723c8b24092 100644
--- a/ports/geckolib/Cargo.lock
+++ b/ports/geckolib/Cargo.lock
@@ -4,14 +4,14 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
@@ -32,7 +32,7 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -67,10 +67,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "cssparser"
-version = "0.5.0"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -146,7 +148,7 @@ name = "euclid"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -167,7 +169,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "heapsize"
-version = "0.2.2"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -317,12 +319,14 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "quickersort 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -358,10 +362,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "string_cache"
-version = "0.2.5"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "debug_unreachable 0.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_generator 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_shared 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -374,10 +380,12 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -388,7 +396,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style_traits 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -399,8 +407,10 @@ dependencies = [
 name = "style_traits"
 version = "0.0.1"
 dependencies = [
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -454,6 +464,8 @@ name = "url"
 version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -468,9 +480,11 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "kernel32-sys 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -485,7 +499,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "uuid 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
diff --git a/ports/geckolib/Cargo.toml b/ports/geckolib/Cargo.toml
index 3e5d754c718..5a511a004c0 100644
--- a/ports/geckolib/Cargo.toml
+++ b/ports/geckolib/Cargo.toml
@@ -11,15 +11,15 @@ crate-type = ["staticlib"]
 [dependencies]
 app_units = {version = "0.2", features = ["plugins"]}
 bitflags = "0.3"
-cssparser = { version = "0.5", features = [ "serde-serialization" ] }
+cssparser = {version = "0.5.2", features = ["heap_size", "serde-serialization"]}
 euclid = {version = "0.6.1", features = ["plugins"]}
 libc = "0.2"
 log = "0.3"
 num_cpus = "0.2.2"
-selectors = "0.4.1"
+selectors = {version = "0.4.1", features = ["heap_size"]}
 smallvec = "0.1"
-string_cache = "0.2"
-url = "0.5.4"
+string_cache = {version = "0.2.7", features = ["heap_size"]}
+url = {version = "0.5.4", features = ["heap_size"]}
 
 [dependencies.util]
 path = "../../components/util"
diff --git a/ports/glutin/Cargo.toml b/ports/glutin/Cargo.toml
index 6bc2f3be2e7..c0713022b14 100644
--- a/ports/glutin/Cargo.toml
+++ b/ports/glutin/Cargo.toml
@@ -13,7 +13,7 @@ headless = ["servo-glutin/headless"]
 
 [dependencies]
 bitflags = "0.3"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 gleam = "0.2"
 euclid = {version = "0.6.1", features = ["plugins"]}
 servo-glutin = "0.4"
diff --git a/ports/gonk/Cargo.lock b/ports/gonk/Cargo.lock
index b9e65f6d501..09893b87e30 100644
--- a/ports/gonk/Cargo.lock
+++ b/ports/gonk/Cargo.lock
@@ -60,7 +60,7 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -82,7 +82,7 @@ dependencies = [
  "core-text 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "freetype 0.1.0 (git+https://github.com/servo/rust-freetype)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -147,9 +147,11 @@ name = "canvas_traits"
 version = "0.0.1"
 dependencies = [
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
@@ -312,10 +314,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "cssparser"
-version = "0.5.0"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -356,6 +360,8 @@ name = "devtools_traits"
 version = "0.0.1"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "msg 0.0.1",
@@ -482,7 +488,7 @@ name = "euclid"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -589,6 +595,8 @@ dependencies = [
  "freetype 0.1.0 (git+https://github.com/servo/rust-freetype)",
  "gfx_traits 0.0.1",
  "harfbuzz-sys 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -607,7 +615,7 @@ dependencies = [
  "servo-skia 0.20130412.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "simd 0.1.0 (git+https://github.com/huonw/simd)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-script 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -621,6 +629,8 @@ version = "0.0.1"
 dependencies = [
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
  "msg 0.0.1",
  "plugins 0.0.1",
@@ -710,7 +720,7 @@ dependencies = [
 
 [[package]]
 name = "heapsize"
-version = "0.2.2"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -731,15 +741,17 @@ dependencies = [
 
 [[package]]
 name = "html5ever"
-version = "0.4.0"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "mac 0.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_codegen 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "tendril 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -831,7 +843,7 @@ name = "js"
 version = "0.1.1"
 source = "git+https://github.com/servo/rust-mozjs#b96675b217534c7742cbfda8150ea0536aedbdfb"
 dependencies = [
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "mozjs_sys 0.0.0 (git+https://github.com/servo/mozjs)",
@@ -869,7 +881,7 @@ dependencies = [
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "glx 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "heapsize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "io-surface 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -889,11 +901,13 @@ dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layout_traits 0.0.1",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -910,7 +924,7 @@ dependencies = [
  "serde_json 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-bidi 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1080,8 +1094,10 @@ name = "msg"
 version = "0.0.1"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.1 (git+https://github.com/servo/rust-layers)",
@@ -1134,6 +1150,8 @@ dependencies = [
 name = "net_traits"
 version = "0.0.1"
 dependencies = [
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
@@ -1419,13 +1437,15 @@ dependencies = [
  "canvas 0.0.1",
  "canvas_traits 0.0.1",
  "caseless 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "devtools_traits 0.0.1",
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
- "html5ever 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "html5ever 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
@@ -1445,7 +1465,7 @@ dependencies = [
  "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicase 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1465,6 +1485,8 @@ dependencies = [
  "devtools_traits 0.0.1",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
@@ -1486,12 +1508,14 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "quickersort 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1692,10 +1716,12 @@ dependencies = [
 
 [[package]]
 name = "string_cache"
-version = "0.2.5"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "debug_unreachable 0.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_generator 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_shared 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1708,10 +1734,12 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1722,7 +1750,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "style_traits 0.0.1",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1733,8 +1761,10 @@ dependencies = [
 name = "style_traits"
 version = "0.0.1"
 dependencies = [
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1849,6 +1879,8 @@ version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "encoding 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1881,10 +1913,12 @@ dependencies = [
  "app_units 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "azure 0.4.0 (git+https://github.com/servo/rust-azure)",
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "html5ever 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "html5ever 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "js 0.1.1 (git+https://github.com/servo/rust-mozjs)",
@@ -1902,7 +1936,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "uuid 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -2044,7 +2078,7 @@ dependencies = [
  "phf 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_codegen 0.7.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "string_cache 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "tendril 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
diff --git a/ports/gonk/Cargo.toml b/ports/gonk/Cargo.toml
index 7a58e64fa99..b153f530ab7 100644
--- a/ports/gonk/Cargo.toml
+++ b/ports/gonk/Cargo.toml
@@ -46,7 +46,7 @@ features = ["non-geckolib"]
 
 [dependencies]
 env_logger = "0.3"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 time = "0.1.17"
 errno = "0.1"
 libc = "0.2"
diff --git a/tests/unit/net/Cargo.toml b/tests/unit/net/Cargo.toml
index bc1d49dade6..eb585685388 100644
--- a/tests/unit/net/Cargo.toml
+++ b/tests/unit/net/Cargo.toml
@@ -32,6 +32,6 @@ git = "https://github.com/servo/ipc-channel"
 [dependencies]
 cookie = "0.2"
 hyper = "0.7"
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
 time = "0.1"
 flate2 = "0.2.0"
diff --git a/tests/unit/plugin/Cargo.toml b/tests/unit/plugin/Cargo.toml
index 286b918c476..19466cd7516 100644
--- a/tests/unit/plugin/Cargo.toml
+++ b/tests/unit/plugin/Cargo.toml
@@ -12,4 +12,4 @@ doctest = false
 path = "../../../components/plugins"
 
 [dependencies]
-url = "0.5.4"
+url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/tests/unit/script/size_of.rs b/tests/unit/script/size_of.rs
index b89ca9dd837..f760d610862 100644
--- a/tests/unit/script/size_of.rs
+++ b/tests/unit/script/size_of.rs
@@ -38,10 +38,10 @@ macro_rules! sizeof_checker (
 
 // Update the sizes here
 sizeof_checker!(size_event_target, EventTarget, 40);
-sizeof_checker!(size_node, Node, 168);
-sizeof_checker!(size_element, Element, 312);
-sizeof_checker!(size_htmlelement, HTMLElement, 328);
-sizeof_checker!(size_div, HTMLDivElement, 328);
-sizeof_checker!(size_span, HTMLSpanElement, 328);
-sizeof_checker!(size_text, Text, 200);
-sizeof_checker!(size_characterdata, CharacterData, 200);
+sizeof_checker!(size_node, Node, 160);
+sizeof_checker!(size_element, Element, 304);
+sizeof_checker!(size_htmlelement, HTMLElement, 320);
+sizeof_checker!(size_div, HTMLDivElement, 320);
+sizeof_checker!(size_span, HTMLSpanElement, 320);
+sizeof_checker!(size_text, Text, 192);
+sizeof_checker!(size_characterdata, CharacterData, 192);
diff --git a/tests/unit/style/Cargo.toml b/tests/unit/style/Cargo.toml
index 9be4fb4eb30..0365fe27b94 100644
--- a/tests/unit/style/Cargo.toml
+++ b/tests/unit/style/Cargo.toml
@@ -25,8 +25,8 @@ path = "../../../components/util"
 
 [dependencies]
 app_units = {version = "0.2", features = ["plugins"]}
-url = "0.5.4"
-cssparser = "0.5"
-selectors = "0.4.1"
-string_cache = "0.2"
+url = {version = "0.5.4", features = ["heap_size"]}
+cssparser = {version = "0.5.2", features = ["heap_size"]}
+selectors = {version = "0.4.1", features = ["heap_size"]}
+string_cache = {version = "0.2.7", features = ["heap_size"]}
 euclid = {version = "0.6.1", features = ["plugins"]}
diff --git a/tests/unit/util/lib.rs b/tests/unit/util/lib.rs
index b42b58ddd7b..72ca23df7ca 100644
--- a/tests/unit/util/lib.rs
+++ b/tests/unit/util/lib.rs
@@ -16,6 +16,5 @@ extern crate util;
 #[cfg(test)] mod logical_geometry;
 #[cfg(test)] mod thread;
 #[cfg(test)] mod vec;
-#[cfg(test)] mod mem;
 #[cfg(test)] mod str;
 #[cfg(test)] mod opts;
diff --git a/tests/unit/util/mem.rs b/tests/unit/util/mem.rs
deleted file mode 100644
index 9b9ac4729e1..00000000000
--- a/tests/unit/util/mem.rs
+++ /dev/null
@@ -1,106 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-use libc::c_void;
-use util::mem::{HeapSizeOf, heap_size_of};
-
-struct Four;
-impl HeapSizeOf for Four {
-    fn heap_size_of_children(&self) -> usize {
-        4
-    }
-}
-
-#[derive(HeapSizeOf)]
-struct Eight(Four, Four, bool, bool, bool);
-
-#[derive(HeapSizeOf)]
-enum EightOrFour {
-    Eight(Eight),
-    Four(Four),
-    Zero(u8)
-}
-
-#[test]
-fn test_heap_size() {
-
-    // Note: jemalloc often rounds up request sizes. However, it does not round up for request
-    // sizes of 8 and higher that are powers of two. We take advantage of knowledge here to make
-    // the sizes of various heap-allocated blocks predictable.
-
-    //-----------------------------------------------------------------------
-    // Start with basic heap block measurement.
-
-    unsafe {
-        // EMPTY is the special non-null address used to represent zero-size allocations.
-        assert_eq!(heap_size_of(::alloc::heap::EMPTY as *const c_void), 0);
-
-        // A 64 byte request is allocated exactly.
-        let x = ::alloc::heap::allocate(64, 0);
-        assert_eq!(heap_size_of(x as *const c_void), 64);
-        ::alloc::heap::deallocate(x, 64, 0);
-
-        // A 255 byte request is rounded up to 256 bytes.
-        let x = ::alloc::heap::allocate(255, 0);
-        assert_eq!(heap_size_of(x as *const c_void), 256);
-        ::alloc::heap::deallocate(x, 255, 0);
-
-        // A 1MiB request is allocated exactly.
-        let x = ::alloc::heap::allocate(1024 * 1024, 0);
-        assert_eq!(heap_size_of(x as *const c_void), 1024 * 1024);
-        ::alloc::heap::deallocate(x, 1024 * 1024, 0);
-    }
-
-    //-----------------------------------------------------------------------
-    // Test HeapSizeOf implementations for various built-in types.
-
-    // Not on the heap; 0 bytes.
-    let x = 0i64;
-    assert_eq!(x.heap_size_of_children(), 0);
-
-    // An i64 is 8 bytes.
-    let x = Box::new(0i64);
-    assert_eq!(x.heap_size_of_children(), 8);
-
-    // An ascii string with 16 chars is 16 bytes in UTF-8.
-    assert_eq!(String::from("0123456789abcdef").heap_size_of_children(), 16);
-
-    // Not on the heap.
-    let x: Option<i32> = None;
-    assert_eq!(x.heap_size_of_children(), 0);
-
-    // Not on the heap.
-    let x = Some(0i64);
-    assert_eq!(x.heap_size_of_children(), 0);
-
-    // The `Some` is not on the heap, but the Box is.
-    let x = Some(Box::new(0i64));
-    assert_eq!(x.heap_size_of_children(), 8);
-
-    // Not on the heap.
-    let x = ::std::sync::Arc::new(0i64);
-    assert_eq!(x.heap_size_of_children(), 0);
-
-    // The `Arc` is not on the heap, but the Box is.
-    let x = ::std::sync::Arc::new(Box::new(0i64));
-    assert_eq!(x.heap_size_of_children(), 8);
-
-    // Zero elements, no heap storage.
-    let x: Vec<i64> = vec![];
-    assert_eq!(x.heap_size_of_children(), 0);
-
-    // Four elements, 8 bytes per element.
-    let x = vec![0i64, 1i64, 2i64, 3i64];
-    assert_eq!(x.heap_size_of_children(), 32);
-
-    //-----------------------------------------------------------------------
-    // Test the HeapSizeOf auto-deriving.
-
-    assert_eq!(Four.heap_size_of_children(), 4);
-    let eight = Eight(Four, Four, true, true, true);
-    assert_eq!(eight.heap_size_of_children(), 8);
-    assert_eq!(EightOrFour::Eight(eight).heap_size_of_children(), 8);
-    assert_eq!(EightOrFour::Four(Four).heap_size_of_children(), 4);
-    assert_eq!(EightOrFour::Zero(1).heap_size_of_children(), 0);
-}