Auto merge of #20132 - nakul02:issue_19223, r=jdm

Profiler for blocked IpcReceiver::recv()

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Implements feature #19223

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #19223 (github issue number if applicable).

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- [x] There are tests for these changes

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WIP.
@jdm - this is the new profiler : "Blocked at IPC Receive"
Should I dig through all the calls to `ipc::channel` and replace them with this profiled `IpcReceiver`?

![screenshot from 2018-02-27 01-35-37](https://user-images.githubusercontent.com/5394361/36721061-b46edea4-1b5e-11e8-91d6-7faba742f237.png)

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1 files changed, 3 insertions, 2 deletions

diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 9496670238b..c866664cbcf 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -15,6 +15,7 @@ use dom::bindings::conversions::ConversionResult;
 use dom::bindings::error::{Error, Fallible};
 use dom::bindings::inheritance::Castable;
 use dom::bindings::num::Finite;
+use dom::bindings::reflector::DomObject;
 use dom::bindings::root::{Dom, DomRoot, LayoutDom};
 use dom::bindings::str::DOMString;
 use dom::canvasrenderingcontext2d::{CanvasRenderingContext2D, LayoutCanvasRenderingContext2DHelpers};
@@ -31,10 +32,10 @@ use euclid::Size2D;
 use html5ever::{LocalName, Prefix};
 use image::ColorType;
 use image::png::PNGEncoder;
-use ipc_channel::ipc;
 use js::error::throw_type_error;
 use js::jsapi::{HandleValue, JSContext};
 use offscreen_gl_context::GLContextAttributes;
+use profile_traits::ipc;
 use script_layout_interface::{HTMLCanvasData, HTMLCanvasDataSource};
 use servo_config::prefs::PREFS;
 use std::iter::repeat;
@@ -258,7 +259,7 @@ impl HTMLCanvasElement {
 
         let data = match self.context.borrow().as_ref() {
             Some(&CanvasContext::Context2d(ref context)) => {
-                let (sender, receiver) = ipc::channel().unwrap();
+                let (sender, receiver) = ipc::channel(self.global().time_profiler_chan().clone()).unwrap();
                 let msg = CanvasMsg::FromScript(FromScriptMsg::SendPixels(sender));
                 context.get_ipc_renderer().send(msg).unwrap();