Web Animations CSS: Unfreeze AnimationClock if sampling timelines does not trigger style recalc

Source/core/animation/DocumentTimeline.cpp

Index: Source/core/animation/DocumentTimeline.cpp
diff --git a/Source/core/animation/DocumentTimeline.cpp b/Source/core/animation/DocumentTimeline.cpp
index 1681ef4a4b74a5b0b9319b25542fd1dad63b9062..e8ee68655f3c8d2ac72ceb0c8502cf5bdcef0ae5 100644
--- a/Source/core/animation/DocumentTimeline.cpp
+++ b/Source/core/animation/DocumentTimeline.cpp
@@ -77,19 +77,20 @@ void DocumentTimeline::wake()
     m_timing->serviceOnNextFrame();
 }
 
-void DocumentTimeline::serviceAnimations(double monotonicAnimationStartTime)
+bool DocumentTimeline::serviceAnimations()
 {
     TRACE_EVENT0("webkit", "DocumentTimeline::serviceAnimations");
 
     m_timing->cancelWake();
 
-    m_document->animationClock().updateTime(monotonicAnimationStartTime);
-
     double timeToNextEffect = std::numeric_limits<double>::infinity();
-    double playerNextEffect;
+    bool didTriggerStyleRecalc = false;
     for (int i = m_players.size() - 1; i >= 0; --i) {
-        if (!m_players[i]->update(&playerNextEffect))
+        double playerNextEffect;
+        bool playerDidTriggerStyleRecalc;
+        if (!m_players[i]->update(&playerNextEffect, &playerDidTriggerStyleRecalc))
             m_players.remove(i);
+        didTriggerStyleRecalc |= playerDidTriggerStyleRecalc;
         if (playerNextEffect < timeToNextEffect)
             timeToNextEffect = playerNextEffect;
     }
@@ -103,6 +104,8 @@ void DocumentTimeline::serviceAnimations(double monotonicAnimationStartTime)
 
     if (m_document->view() && !m_players.isEmpty())
         m_document->view()->scheduleAnimation();
+
+    return didTriggerStyleRecalc;
 }
 
 void DocumentTimeline::setZeroTime(double zeroTime)