Ensure serviceOnNextFrame isn't put off indefinitely.

Source/core/animation/AnimationTimeline.cpp

Index: Source/core/animation/AnimationTimeline.cpp
diff --git a/Source/core/animation/AnimationTimeline.cpp b/Source/core/animation/AnimationTimeline.cpp
index dd7057a56e7d7f72f0abb5483a5ef455c5fbf34a..28548a928b31314deb2e781a48c3269f7d3543fb 100644
--- a/Source/core/animation/AnimationTimeline.cpp
+++ b/Source/core/animation/AnimationTimeline.cpp
@@ -174,6 +174,8 @@ void AnimationTimeline::scheduleNextService()
 
 void AnimationTimeline::AnimationTimelineTiming::wakeAfter(double duration)
 {
+    if (m_timer.isActive() && m_timer.nextFireInterval() < duration)
+        return;
     m_timer.startOneShot(duration, FROM_HERE);
 }