The WPT test at imported/w3c/web-platform-tests/web-animations need to all pass reliably. Here are the current sub-tasks for this:

* animation-model/animation-types/accumulation-per-property.html (webkit.org/b/186485)
* animation-model/animation-types/addition-per-property.html (webkit.org/b/186486)
* animation-model/animation-types/discrete.html (webkit.org/b/186487)
* animation-model/animation-types/interpolation-per-property.html (webkit.org/b/186488)
* animation-model/combining-effects/effect-composition.html (webkit.org/b/186489)
* animation-model/keyframe-effects/effect-value-context.html (webkit.org/b/186490)
* animation-model/keyframe-effects/effect-value-iteration-composite-operation.html (webkit.org/b/186491)
* animation-model/keyframe-effects/effect-value-overlapping-keyframes.html (webkit.org/b/186492)
* animation-model/keyframe-effects/effect-value-transformed-distance.html (webkit.org/b/186493)
* interfaces/Animatable/animate-no-browsing-context.html (webkit.org/b/186494)
* interfaces/Animatable/animate.html (webkit.org/b/186495)
* interfaces/Animation/finish.html (webkit.org/b/186496)
* interfaces/Animation/finished.html (webkit.org/b/186497)
* interfaces/DocumentTimeline/constructor.html (webkit.org/b/186498)
* interfaces/KeyframeEffect/constructor.html (webkit.org/b/186499)
* interfaces/KeyframeEffect/iterationComposite.html (webkit.org/b/186500)
* interfaces/KeyframeEffect/processing-a-keyframes-argument-001.html (webkit.org/b/186501)
* interfaces/KeyframeEffect/processing-a-keyframes-argument-002.html (webkit.org/b/186502)
* interfaces/KeyframeEffect/setKeyframes.html (webkit.org/b/186503)
* timing-model/animations/canceling-an-animation.html (webkit.org/b/186504)
* timing-model/animations/current-time.html (webkit.org/b/186505)
* timing-model/animations/set-the-animation-start-time.html (webkit.org/b/186506)
* timing-model/timelines/document-timelines.html (webkit.org/b/186507)
* timing-model/timelines/timelines.html (webkit.org/b/186508)