Web Animations CSS: Start running animations on the compositor

LayoutTests/TestExpectations

Index: LayoutTests/TestExpectations
diff --git a/LayoutTests/TestExpectations b/LayoutTests/TestExpectations
index f484822aa117ed0e991885185de7e228f7d4dfae..ddce443416114ff2ea597b57208c62bb55b60c70 100644
--- a/LayoutTests/TestExpectations
+++ b/LayoutTests/TestExpectations
@@ -55,6 +55,7 @@ crbug.com/264138 dom/xhtml/level3/core/nodecomparedocumentposition38.xhtml [ Fai
 # The implementation of CSS Animations on the Web Animations model is still in progress
 # This test fails due to -webkit-mask-box-image not being implemented as a shorthand property
 crbug.com/309962 virtual/web-animations-css/animations/cross-fade-webkit-mask-box-image.html [ ImageOnlyFailure ]
+crbug.com/298211 virtual/web-animations-css/animations/keyframe-multiple-timing-functions-transform.html [ NeedsRebaseline ]
 
 crbug.com/305070 [ Debug ] animations/interpolation/svg-stroke-dasharray-interpolation.html [ Crash Pass ]
 crbug.com/305070 [ Debug ] virtual/threaded/animations/interpolation/svg-stroke-dasharray-interpolation.html [ Crash Pass ]
@@ -591,9 +592,6 @@ crbug.com/310992 animations/play-state.html [ Pass Failure ]
 crbug.com/310992 virtual/threaded/animations/play-state.html [ Pass Failure ]
 crbug.com/310992 virtual/web-animations-css/animations/play-state.html [ Pass Failure ]
 
-# This can't be rebaselined because it's a reftest.
-crbug.com/311423 animations/opacity-transform-animation.html [ ImageOnlyFailure ]
-
 crbug.com/309369 perf/accessibility-title-ui-element.html [ Pass Timeout ]
 crbug.com/309370 [ Mac ] fast/css/font-face-html-as-svg.html [ Timeout ]
 crbug.com/310292 [ Mac ] http/tests/security/video-poster-cross-origin-crash.html [ Failure Pass ]