Web Animations CSS: Start running animations on the compositor

Source/core/animation/DocumentTimeline.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 139 matching lines @@
 void DocumentTimeline::dispatchEvents()
 {
     Vector<EventToDispatch> events = m_events;
     m_events.clear();
     for (size_t i = 0; i < events.size(); i++)
         events[i].target->dispatchEvent(events[i].event.release());
 }
 
 size_t DocumentTimeline::numberOfActiveAnimationsForTesting() const
 {
+    if (isNull(m_zeroTime))
+        return 0;
     // Includes all players whose directly associated timed items
     // are current or in effect.
     if (isNull(m_zeroTime))
         return 0;
     size_t count = 0;
     for (size_t i = 0; i < m_players.size(); ++i) {
         const TimedItem* timedItem = m_players[i]->source();
-        count += (timedItem && (timedItem->isCurrent() || timedItem->isInEffect()));
+        if (m_players[i]->hasStartTime())
+            count += (timedItem && (timedItem->isCurrent() || timedItem->isInEffect()));
     }
     return count;
 }
 
 } // namespace