Animation: Composite animations with any start delay specified

Source/core/animation/CompositorAnimationsImpl.h

 /*
  * 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 23 matching lines @@
 #include "platform/animation/TimingFunction.h"
 #include "public/platform/WebCompositorAnimation.h"
 
 namespace blink {
 
 class WebCompositorAnimationCurve;
 
 class CompositorAnimationsImpl {
 private:
     struct CompositorTiming {
+        void assertValid() const
+        {
+            ASSERT(scaledDuration > 0);
+            ASSERT(std::isfinite(scaledTimeOffset));
+            ASSERT(adjustedIterationCount > 0 || adjustedIterationCount == -1);
+            ASSERT(std::isfinite(playbackRate) && playbackRate);
+            ASSERT(iterationStart >= 0);
+        }
+
         Timing::PlaybackDirection direction;
         double scaledDuration;
         double scaledTimeOffset;
         double adjustedIterationCount;
         double playbackRate;
         Timing::FillMode fillMode;
         double iterationStart;
     };
 
     static bool convertTimingForCompositor(const Timing&, double timeOffset, CompositorTiming& out, double playerPlaybackRate);
 
     static void getAnimationOnCompositor(const Timing&, double startTime, double timeOffset, const KeyframeEffectModelBase&, Vector<OwnPtr<WebCompositorAnimation> >& animations, double playerPlaybackRate);
 
     static void addKeyframesToCurve(WebCompositorAnimationCurve&, const AnimatableValuePropertySpecificKeyframeVector&, const Timing&);
 
     friend class CompositorAnimations;
     friend class AnimationCompositorAnimationsTest;
 };
 
 } // namespace blink