Animations: Disable compositor when timeline playback rate is set

This change invalidates all compositor animations when the animation
timeline playback rate is modified. If the timeline playback rate is not
1, then animations are no longer composited.

BUG=432368

Review URL: https://codereview.chromium.org/722203004

git-svn-id: svn://svn.chromium.org/blink/trunk@185424 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/animation/AnimationPlayer.cpp

@@ -599,7 +599,8 @@ void AnimationPlayer::setOutdated()
 
 bool AnimationPlayer::canStartAnimationOnCompositor()
 {
-    if (m_playbackRate == 0 || (std::isinf(sourceEnd()) && m_playbackRate < 0))
+    // FIXME: Timeline playback rates should be compositable
+    if (m_playbackRate == 0 || (std::isinf(sourceEnd()) && m_playbackRate < 0) || (timeline() && timeline()->playbackRate() != 1))
         return false;
 
     return m_timeline && m_content && m_content->isAnimation() && playing();

third_party/WebKit/Source/core/animation/AnimationTimeline.cpp

@@ -236,10 +236,12 @@ void AnimationTimeline::setOutdatedAnimationPlayer(AnimationPlayer* player)
 
 void AnimationTimeline::setPlaybackRate(double playbackRate)
 {
-    // FIXME: need to invalidate compositor animations
     m_currentTimeSnapshot = currentTimeInternal();
     m_rawCurrentTimeSnapshot = m_document->animationClock().currentTime() - zeroTime();
     m_playbackRate = playbackRate;
+    for (auto& player : m_players) {
+        player->setCompositorPending(true);
+    }
 }
 
 double AnimationTimeline::playbackRate() const