Add EME layout test that tests MediaKeys lifetime

Adding a new layout test for EME that allocates a bunch of MediaKey objects and then forces garbage collection.

BUG=341567
TEST=new layout test passes

Review URL: https://codereview.chromium.org/180203002

git-svn-id: svn://svn.chromium.org/blink/trunk@170718 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add support for element ids in TargetedStyleRecalc.

BUG=318468

Review URL: https://codereview.chromium.org/220123004

git-svn-id: svn://svn.chromium.org/blink/trunk@170719 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[Reland] Web Animations: Introduce String based KeyframeEffectModel

Note: This is a rework of issue 212023004

This patch refactors KeyframeEffectModel to support different types of
keyframe values. The common keyframe logic is retained in
KeyframeEffectModelBase to be inherited by the keyframe type specialisations.

KeyframeEffectModel is then templated on Keyframe type, with a hierarchy of Keyframes
including StringKeyframe and AnimatableValueKeyframe being introduced.

String based keyframes are being introduced to properly support the JS API
for Web Animations element.animate().

Original issue: https://codereview.chromium.org/215883005

TBR=rafaelw,dstockwell

Review URL: https://codereview.chromium.org/217143004

git-svn-id: svn://svn.chromium.org/blink/trunk@170720 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Move subpixelAccumulation from CompositedLayerMapping to RenderLayer.

It is a property specific to a RenderLayer, so this makes more sense. Also,
this makes it possible to properly add in subpixel accumulation when
computing repainting for squashed layers.

BUG=358261

Review URL: https://codereview.chromium.org/222023007

git-svn-id: svn://svn.chromium.org/blink/trunk@170721 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Eliminate FontDescription::setStyle(bool).

It's much clearer to pass a FontStyle enum at the call site, and only a
handful of callers don't do this already.

BUG=

Review URL: https://codereview.chromium.org/213683008

git-svn-id: svn://svn.chromium.org/blink/trunk@170722 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Revert 170619 "Revert r170531"

This CL is relanding r170531.
The Android bot failure was already resolved,
so I'm relanding r170531 and r170536.

> Revert r170531
> 
> r170531 copied files to make the diff of r170536 saner.
> Now that r170536 was reverted, we need to revert r170531 at the same time.
> Otherwise, we'll leave meaningless files in the code base.
> 
> TBR=tkent
> 
> Review URL: https://codereview.chromium.org/221663003

TBR=haraken@chromium.org

Review URL: https://codereview.chromium.org/222613008

git-svn-id: svn://svn.chromium.org/blink/trunk@170723 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Rename DatabaseTaskSynchronizer to TaskSynchronizer and move it to platform/

- We want to use DatabaseTaskSynchronizer in the HTML parser thread in a follow-up CL. In preparation for that, this CL renames DatabaseTaskSynchronizer to TaskSynchronizer and moves it to platform/.

BUG=340522
R=ager@chromium.org, tkent@chromium.org, wibling@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=170532

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=170536

Review URL: https://codereview.chromium.org/198673002

git-svn-id: svn://svn.chromium.org/blink/trunk@170724 bbb929c8-8fbe-4397-9dbb-9b2b20218538