Auto merge of #20254 - servo:derive-all-the-things, r=emilio

Some random improvements to derived style code

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13 files changed, 93 insertions, 117 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 28f9407074d..cbf5c1a7973 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -94,7 +94,7 @@ version = "0.28.0"
 source = "git+https://github.com/servo/rust-azure#29f0c063ad366b5364e06af26d3e9d1ee588e3b2"
 dependencies = [
  "cmake 0.1.29 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
  "servo-freetype-sys 4.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "servo-skia 0.30000013.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -272,7 +272,7 @@ dependencies = [
  "canvas_traits 0.0.1",
  "compositing 0.0.1",
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -289,7 +289,7 @@ name = "canvas_traits"
 version = "0.0.1"
 dependencies = [
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "malloc_size_of 0.0.1",
@@ -419,7 +419,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 name = "compositing"
 version = "0.0.1"
 dependencies = [
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.18.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -452,7 +452,7 @@ dependencies = [
  "compositing 0.0.1",
  "debugger 0.0.1",
  "devtools_traits 0.0.1",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gaol 0.0.1 (git+https://github.com/servo/gaol)",
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
@@ -859,7 +859,7 @@ dependencies = [
 
 [[package]]
 name = "euclid"
-version = "0.17.1"
+version = "0.17.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "num-traits 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1006,7 +1006,7 @@ dependencies = [
  "core-graphics 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-text 9.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dwrote 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "fontsan 0.4.0 (git+https://github.com/servo/fontsan)",
  "freetype 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1390,7 +1390,7 @@ dependencies = [
  "atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas_traits 0.0.1",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
@@ -1432,7 +1432,7 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
@@ -1547,7 +1547,7 @@ dependencies = [
  "devtools 0.0.1",
  "devtools_traits 0.0.1",
  "env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gaol 0.0.1 (git+https://github.com/servo/gaol)",
  "gfx 0.0.1",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1625,7 +1625,7 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hashglobe 0.1.0",
  "mozjs 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "selectors 0.19.0",
@@ -2019,7 +2019,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cgl 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-foundation 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gl_generator 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2184,7 +2184,7 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "binary-space-partition 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -2441,7 +2441,7 @@ dependencies = [
  "dom_struct 0.0.1",
  "domobject_derive 0.0.1",
  "encoding_rs 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "half 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2509,7 +2509,7 @@ dependencies = [
  "atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas_traits 0.0.1",
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
  "html5ever 0.22.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2546,7 +2546,7 @@ dependencies = [
 name = "script_tests"
 version = "0.0.1"
 dependencies = [
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
  "script 0.0.1",
  "servo_url 0.0.1",
@@ -2561,7 +2561,7 @@ dependencies = [
  "canvas_traits 0.0.1",
  "cookie 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "devtools_traits 0.0.1",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
  "hyper 0.10.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper_serde 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2658,7 +2658,7 @@ dependencies = [
  "backtrace 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "compositing 0.0.1",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gdi32-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "glutin 0.13.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2725,7 +2725,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cgl 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "cmake 0.1.29 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "expat-sys 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "glutin 0.13.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2786,7 +2786,7 @@ version = "0.0.1"
 dependencies = [
  "android_injected_glue 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2804,7 +2804,7 @@ name = "servo_geometry"
 version = "0.0.1"
 dependencies = [
  "app_units 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "malloc_size_of 0.0.1",
  "malloc_size_of_derive 0.0.1",
  "webrender_api 0.57.0 (git+https://github.com/servo/webrender)",
@@ -2948,7 +2948,7 @@ dependencies = [
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "debug_unreachable 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding_rs 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fallible 0.0.1",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "hashglobe 0.1.0",
@@ -3008,7 +3008,7 @@ dependencies = [
  "app_units 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "html5ever 0.22.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3030,7 +3030,7 @@ dependencies = [
  "app_units 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "malloc_size_of 0.0.1",
  "malloc_size_of_derive 0.0.1",
  "selectors 0.19.0",
@@ -3048,7 +3048,7 @@ dependencies = [
  "cssparser 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "cstr 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "geckoservo 0.0.1",
  "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3450,7 +3450,7 @@ version = "0.0.1"
 dependencies = [
  "base64 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cookie 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.10.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.18.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3480,7 +3480,7 @@ dependencies = [
  "core-graphics 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-text 9.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dwrote 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "freetype 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "fxhash 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.4.23 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3507,7 +3507,7 @@ dependencies = [
  "core-foundation 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-graphics 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dwrote 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3519,7 +3519,7 @@ name = "webvr"
 version = "0.0.1"
 dependencies = [
  "canvas_traits 0.0.1",
- "euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
@@ -3767,7 +3767,7 @@ dependencies = [
 "checksum enum_primitive 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "be4551092f4d519593039259a9ed8daedf0da12e5109c5280338073eaeb81180"
 "checksum env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3ddf21e73e016298f5cb37d6ef8e8da8e39f91f9ec8b0df44b7deb16a9f8cd5b"
 "checksum error-chain 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d9435d864e017c3c6afeac1654189b06cdb491cf2ff73dbf0d73b0f292f42ff8"
-"checksum euclid 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5069a1354a7eecfdedc97e8e931b1fc455c4d06f5910380a3a049327ca7a0d0a"
+"checksum euclid 0.17.2 (registry+https://github.com/rust-lang/crates.io-index)" = "adfe67a9343519c1449d208da5998c6de582de698f7a39c4ac82ffba23d131a5"
 "checksum expat-sys 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "c470ccb972f2088549b023db8029ed9da9426f5affbf9b62efff7009ab8ed5b1"
 "checksum flate2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9fac2277e84e5e858483756647a9d0aa8d9a2b7cba517fd84325a0aaa69a0909"
 "checksum fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6cc484842f1e2884faf56f529f960cc12ad8c71ce96cc7abba0a067c98fee344"
diff --git a/components/style/gecko/url.rs b/components/style/gecko/url.rs
index e737b29926b..2642e174b01 100644
--- a/components/style/gecko/url.rs
+++ b/components/style/gecko/url.rs
@@ -121,7 +121,7 @@ impl MallocSizeOf for CssUrl {
 }
 
 /// A specified url() value for general usage.
-#[derive(Clone, Debug, ToCss)]
+#[derive(Clone, Debug, ToComputedValue, ToCss)]
 pub struct SpecifiedUrl {
     /// The specified url value.
     pub url: CssUrl,
@@ -130,7 +130,6 @@ pub struct SpecifiedUrl {
     #[css(skip)]
     pub url_value: RefPtr<URLValue>,
 }
-trivial_to_computed_value!(SpecifiedUrl);
 
 impl SpecifiedUrl {
     fn from_css_url(url: CssUrl) -> Self {
@@ -177,7 +176,7 @@ impl MallocSizeOf for SpecifiedUrl {
 /// A specified url() value for image.
 ///
 /// This exists so that we can construct `ImageValue` and reuse it.
-#[derive(Clone, Debug, ToCss)]
+#[derive(Clone, Debug, ToComputedValue, ToCss)]
 pub struct SpecifiedImageUrl {
     /// The specified url value.
     pub url: CssUrl,
@@ -186,7 +185,6 @@ pub struct SpecifiedImageUrl {
     #[css(skip)]
     pub image_value: RefPtr<ImageValue>,
 }
-trivial_to_computed_value!(SpecifiedImageUrl);
 
 impl SpecifiedImageUrl {
     fn from_css_url(url: CssUrl) -> Self {
diff --git a/components/style/properties/helpers/animated_properties.mako.rs b/components/style/properties/helpers/animated_properties.mako.rs
index 02fe6b2ba0e..570658c5301 100644
--- a/components/style/properties/helpers/animated_properties.mako.rs
+++ b/components/style/properties/helpers/animated_properties.mako.rs
@@ -78,7 +78,7 @@ pub fn nscsspropertyid_is_animatable(property: nsCSSPropertyID) -> bool {
 /// a shorthand with at least one transitionable longhand component, or an unsupported property.
 // NB: This needs to be here because it needs all the longhands generated
 // beforehand.
-#[derive(Clone, Debug, Eq, Hash, MallocSizeOf, PartialEq, ToCss)]
+#[derive(Clone, Debug, Eq, Hash, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
 pub enum TransitionProperty {
     /// A shorthand.
     Shorthand(ShorthandId),
@@ -89,8 +89,6 @@ pub enum TransitionProperty {
     Unsupported(CustomIdent),
 }
 
-trivial_to_computed_value!(TransitionProperty);
-
 impl TransitionProperty {
     /// Returns `all`.
     #[inline]
diff --git a/components/style/values/animated/mod.rs b/components/style/values/animated/mod.rs
index 04bab7375f1..ad81a4ecc4a 100644
--- a/components/style/values/animated/mod.rs
+++ b/components/style/values/animated/mod.rs
@@ -159,7 +159,7 @@ impl Animate for Au {
 
 impl<T> Animate for Size2D<T>
 where
-    T: Animate + Copy,
+    T: Animate,
 {
     #[inline]
     fn animate(&self, other: &Self, procedure: Procedure) -> Result<Self, ()> {
@@ -172,7 +172,7 @@ where
 
 impl<T> Animate for Point2D<T>
 where
-    T: Animate + Copy,
+    T: Animate,
 {
     #[inline]
     fn animate(&self, other: &Self, procedure: Procedure) -> Result<Self, ()> {
diff --git a/components/style/values/computed/mod.rs b/components/style/values/computed/mod.rs
index 1667f7ec8cf..ff16e328826 100644
--- a/components/style/values/computed/mod.rs
+++ b/components/style/values/computed/mod.rs
@@ -428,7 +428,6 @@ trivial_to_computed_value!(u8);
 trivial_to_computed_value!(u16);
 trivial_to_computed_value!(u32);
 trivial_to_computed_value!(Atom);
-trivial_to_computed_value!(BorderStyle);
 trivial_to_computed_value!(CursorKind);
 #[cfg(feature = "servo")]
 trivial_to_computed_value!(Prefix);
diff --git a/components/style/values/generics/basic_shape.rs b/components/style/values/generics/basic_shape.rs
index e653508390f..ef9eac14ec7 100644
--- a/components/style/values/generics/basic_shape.rs
+++ b/components/style/values/generics/basic_shape.rs
@@ -18,7 +18,7 @@ pub type ClippingShape<BasicShape, Url> = ShapeSource<BasicShape, GeometryBox, U
 
 /// <https://drafts.fxtf.org/css-masking-1/#typedef-geometry-box>
 #[allow(missing_docs)]
-#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
+#[derive(Animate, Clone, Copy, Debug, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
 pub enum GeometryBox {
     FillBox,
     StrokeBox,
@@ -32,7 +32,7 @@ pub type FloatAreaShape<BasicShape, Image> = ShapeSource<BasicShape, ShapeBox, I
 /// https://drafts.csswg.org/css-shapes-1/#typedef-shape-box
 #[allow(missing_docs)]
 #[cfg_attr(feature = "servo", derive(Deserialize, Serialize))]
-#[derive(Clone, Copy, Debug, Eq, MallocSizeOf, Parse, PartialEq)]
+#[derive(Animate, Clone, Copy, Debug, Eq, MallocSizeOf, Parse, PartialEq)]
 #[derive(ToComputedValue, ToCss)]
 pub enum ShapeBox {
     MarginBox,
@@ -49,7 +49,6 @@ pub enum ShapeSource<BasicShape, ReferenceBox, ImageOrUrl> {
     ImageOrUrl(ImageOrUrl),
     Shape(
         BasicShape,
-        #[animation(constant)]
         Option<ReferenceBox>,
     ),
     #[animation(error)]
diff --git a/components/style/values/generics/grid.rs b/components/style/values/generics/grid.rs
index 2b519f1aa85..cc3256df7ab 100644
--- a/components/style/values/generics/grid.rs
+++ b/components/style/values/generics/grid.rs
@@ -566,7 +566,7 @@ impl<L: ToCss, I: ToCss> ToCss for TrackList<L, I> {
 ///
 /// `subgrid [ <line-names> | repeat(<positive-integer> | auto-fill, <line-names>+) ]+`
 /// Old spec: https://www.w3.org/TR/2015/WD-css-grid-1-20150917/#typedef-line-name-list
-#[derive(Clone, Debug, Default, MallocSizeOf, PartialEq)]
+#[derive(Clone, Debug, Default, MallocSizeOf, PartialEq, ToComputedValue)]
 pub struct LineNameList {
     /// The optional `<line-name-list>`
     pub names: Box<[Box<[CustomIdent]>]>,
@@ -574,8 +574,6 @@ pub struct LineNameList {
     pub fill_idx: Option<u32>,
 }
 
-trivial_to_computed_value!(LineNameList);
-
 impl Parse for LineNameList {
     fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
         input.expect_ident_matching("subgrid")?;
diff --git a/components/style/values/generics/image.rs b/components/style/values/generics/image.rs
index 75751e39621..7f02fdec4f4 100644
--- a/components/style/values/generics/image.rs
+++ b/components/style/values/generics/image.rs
@@ -132,8 +132,8 @@ pub struct ColorStop<Color, LengthOrPercentage> {
 
 /// Specified values for a paint worklet.
 /// <https://drafts.css-houdini.org/css-paint-api/>
-#[derive(Clone, Debug, PartialEq)]
 #[cfg_attr(feature = "servo", derive(MallocSizeOf))]
+#[derive(Clone, Debug, PartialEq, ToComputedValue)]
 pub struct PaintWorklet {
     /// The name the worklet was registered with.
     pub name: Atom,
@@ -143,8 +143,6 @@ pub struct PaintWorklet {
     pub arguments: Vec<Arc<custom_properties::SpecifiedValue>>,
 }
 
-trivial_to_computed_value!(PaintWorklet);
-
 impl ToCss for PaintWorklet {
     fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
     where
diff --git a/components/style/values/generics/transform.rs b/components/style/values/generics/transform.rs
index 816d8cc4cfd..1d96c9e9d84 100644
--- a/components/style/values/generics/transform.rs
+++ b/components/style/values/generics/transform.rs
@@ -298,7 +298,7 @@ pub enum TransformOperation<Angle, Number, Length, Integer, LengthOrPercentage>
     },
 }
 
-#[derive(Animate, Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
+#[derive(Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
 /// A value of the `transform` property
 pub struct Transform<T>(#[css(if_empty = "none", iterable)] pub Vec<T>);
 
diff --git a/components/style/values/specified/mod.rs b/components/style/values/specified/mod.rs
index 192c22a0a13..f0703699eaf 100644
--- a/components/style/values/specified/mod.rs
+++ b/components/style/values/specified/mod.rs
@@ -158,7 +158,7 @@ fn parse_number_with_clamping_mode<'i, 't>(
 #[allow(missing_docs)]
 #[cfg_attr(feature = "servo", derive(Deserialize, Serialize))]
 #[derive(Clone, Copy, Debug, Eq, MallocSizeOf, Ord, Parse, PartialEq)]
-#[derive(PartialOrd, ToCss)]
+#[derive(PartialOrd, ToComputedValue, ToCss)]
 pub enum BorderStyle {
     None = -1,
     Solid = 6,
diff --git a/components/style/values/specified/position.rs b/components/style/values/specified/position.rs
index 1f337560488..4a614aa1e03 100644
--- a/components/style/values/specified/position.rs
+++ b/components/style/values/specified/position.rs
@@ -509,7 +509,7 @@ impl From<GridAutoFlow> for u8 {
 }
 
 #[cfg_attr(feature = "gecko", derive(MallocSizeOf))]
-#[derive(Clone, Debug, PartialEq, ToCss)]
+#[derive(Clone, Debug, PartialEq, ToComputedValue, ToCss)]
 /// https://drafts.csswg.org/css-grid/#named-grid-area
 pub struct TemplateAreas {
     /// `named area` containing for each template area
@@ -614,10 +614,8 @@ impl Parse for TemplateAreas {
     }
 }
 
-trivial_to_computed_value!(TemplateAreas);
-
 /// Arc type for `Arc<TemplateAreas>`
-#[derive(Clone, Debug, MallocSizeOf, PartialEq, ToCss)]
+#[derive(Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
 pub struct TemplateAreasArc(#[ignore_malloc_size_of = "Arc"] pub Arc<TemplateAreas>);
 
 impl Parse for TemplateAreasArc {
@@ -631,8 +629,6 @@ impl Parse for TemplateAreasArc {
     }
 }
 
-trivial_to_computed_value!(TemplateAreasArc);
-
 #[cfg_attr(feature = "gecko", derive(MallocSizeOf))]
 #[derive(Clone, Debug, PartialEq)]
 /// Not associated with any particular grid item, but can
diff --git a/components/style_derive/animate.rs b/components/style_derive/animate.rs
index f96469c079e..912f7dbc9f2 100644
--- a/components/style_derive/animate.rs
+++ b/components/style_derive/animate.rs
@@ -2,10 +2,10 @@
  * 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 cg;
+use cg::{self, WhereClause};
 use quote::Tokens;
 use syn::{DeriveInput, Path};
-use synstructure;
+use synstructure::{Structure, VariantInfo};
 
 pub fn derive(input: DeriveInput) -> Tokens {
     let name = &input.ident;
@@ -14,62 +14,18 @@ pub fn derive(input: DeriveInput) -> Tokens {
         cg::trait_parts(&input, &trait_path);
 
     let input_attrs = cg::parse_input_attrs::<AnimateInputAttrs>(&input);
-    let s = synstructure::Structure::new(&input);
+    let s = Structure::new(&input);
     let mut append_error_clause = s.variants().len() > 1;
 
     let mut match_body = s.variants().iter().fold(quote!(), |body, variant| {
-        let variant_attrs = cg::parse_variant_attrs::<AnimationVariantAttrs>(&variant.ast());
-        if variant_attrs.error {
-            append_error_clause = true;
-            return body;
-        }
-        let (this_pattern, this_info) = cg::ref_pattern(&variant, "this");
-        let (other_pattern, other_info) = cg::ref_pattern(&variant, "other");
-        let (result_value, result_info) = cg::value(&variant, "result");
-        let mut computations = quote!();
-        let iter = result_info.iter().zip(this_info.iter().zip(&other_info));
-        computations.append_all(iter.map(|(result, (this, other))| {
-            let field_attrs = cg::parse_field_attrs::<AnimationFieldAttrs>(&result.ast());
-            if field_attrs.constant {
-                if cg::is_parameterized(&result.ast().ty, &where_clause.params, None) {
-                    cg::add_predicate(
-                        &mut where_clause.inner,
-                        cg::where_predicate(
-                            result.ast().ty.clone(),
-                            &parse_quote!(std::cmp::PartialEq),
-                            None,
-                        ),
-                    );
-                    cg::add_predicate(
-                        &mut where_clause.inner,
-                        cg::where_predicate(
-                            result.ast().ty.clone(),
-                            &parse_quote!(std::clone::Clone),
-                            None,
-                        ),
-                    );
-                }
-                quote! {
-                    if #this != #other {
-                        return Err(());
-                    }
-                    let #result = ::std::clone::Clone::clone(#this);
-                }
-            } else {
-                where_clause.add_trait_bound(&result.ast().ty);
-                quote! {
-                    let #result =
-                        ::values::animated::Animate::animate(#this, #other, procedure)?;
-                }
+        let arm = match derive_variant_arm(variant, &mut where_clause) {
+            Ok(arm) => arm,
+            Err(()) => {
+                append_error_clause = true;
+                return body;
             }
-        }));
-        quote! {
-            #body
-            (&#this_pattern, &#other_pattern) => {
-                #computations
-                Ok(#result_value)
-            }
-        }
+        };
+        quote! { #body #arm }
     });
 
     if append_error_clause {
@@ -99,6 +55,44 @@ pub fn derive(input: DeriveInput) -> Tokens {
     }
 }
 
+fn derive_variant_arm(
+    variant: &VariantInfo,
+    where_clause: &mut WhereClause,
+) -> Result<Tokens, ()> {
+    let variant_attrs = cg::parse_variant_attrs::<AnimationVariantAttrs>(&variant.ast());
+    if variant_attrs.error {
+        return Err(());
+    }
+    let (this_pattern, this_info) = cg::ref_pattern(&variant, "this");
+    let (other_pattern, other_info) = cg::ref_pattern(&variant, "other");
+    let (result_value, result_info) = cg::value(&variant, "result");
+    let mut computations = quote!();
+    let iter = result_info.iter().zip(this_info.iter().zip(&other_info));
+    computations.append_all(iter.map(|(result, (this, other))| {
+        let field_attrs = cg::parse_field_attrs::<AnimationFieldAttrs>(&result.ast());
+        if field_attrs.constant {
+            quote! {
+                if #this != #other {
+                    return Err(());
+                }
+                let #result = ::std::clone::Clone::clone(#this);
+            }
+        } else {
+            where_clause.add_trait_bound(&result.ast().ty);
+            quote! {
+                let #result =
+                    ::values::animated::Animate::animate(#this, #other, procedure)?;
+            }
+        }
+    }));
+    Ok(quote! {
+        (&#this_pattern, &#other_pattern) => {
+            #computations
+            Ok(#result_value)
+        }
+    })
+}
+
 #[darling(attributes(animate), default)]
 #[derive(Default, FromDeriveInput)]
 struct AnimateInputAttrs {
diff --git a/components/style_derive/to_css.rs b/components/style_derive/to_css.rs
index 1d3a2f2d230..4f8841810c1 100644
--- a/components/style_derive/to_css.rs
+++ b/components/style_derive/to_css.rs
@@ -5,16 +5,12 @@
 use cg;
 use darling::util::Override;
 use quote::{ToTokens, Tokens};
-use syn::{self, Data, GenericParam, Path, WhereClause};
+use syn::{self, Data, Path, WhereClause};
 use synstructure::{BindingInfo, Structure, VariantInfo};
 
 pub fn derive(mut input: syn::DeriveInput) -> Tokens {
     let mut where_clause = input.generics.where_clause.take();
-    for param in &input.generics.params {
-        let param = match *param {
-            GenericParam::Type(ref param) => param,
-            _ => continue,
-        };
+    for param in input.generics.type_params() {
         cg::add_predicate(
             &mut where_clause,
             parse_quote!(#param: ::style_traits::ToCss),