Auto merge of #11766 - emilio:keyframes-parsing, r=SimonSapin,pcwalton

Add `@keyframes` and `animation-*` support.

- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors

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- [x] There are tests for these changes

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This adds support for parsing `@keyframes` rules, and animation properties. Stylo will need it sometime soonish, plus I want to make animations work in Servo.

The remaining part is doin the math and trigger the animations correctly from servo. I don't expect it to be *that* hard, but probaby I'll need to learn a bit more about the current animation infra (e.g. why the heck is the `new_animations_sender` guarded by a `Mutex`?).

I'd expect to land this, since this is already a bunch of work, this is the part exclusively required by stylo (at least if we don't use Servo's machinery), the media query parsing is tested, and the properties land after a flag, but if you prefer to wait until I finish this up it's fine for me too.

r? @SimonSapin

cc @pcwalton @bholley

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index 6697f334696..96555524c5d 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -671,7 +671,7 @@ impl ScriptThread {
         }
 
         // Store new resizes, and gather all other events.
-        let mut sequential = vec!();
+        let mut sequential = vec![];
 
         // Receive at least one message so we don't spinloop.
         let mut event = {