Share animations from compositor to main thread.

third_party/WebKit/public/platform/WebCompositorAnimationDelegate.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef WebCompositorAnimationDelegate_h
 #define WebCompositorAnimationDelegate_h
 
 #include "WebCommon.h"
+#include "cc/animation/animation_curve.h"
 
 namespace blink {
 
 class BLINK_PLATFORM_EXPORT WebCompositorAnimationDelegate {
 public:
     virtual ~WebCompositorAnimationDelegate() { }
 
     virtual void notifyAnimationStarted(double monotonicTime, int group) = 0;
     virtual void notifyAnimationFinished(double monotonicTime, int group) = 0;
     virtual void notifyAnimationAborted(double monotonicTime, int group) = 0;
+    // In the current state of things, notifyAnimationTakeover only applies to
+    // scroll offset animations since main thread scrolling reasons can be added
+    // while the compositor is animating. Keeping this non-pure virtual since
+    // it doesn't apply to CSS animations.
+    virtual void notifyAnimationTakeover(
+        double monotonicTime,
+        double animationStartTime,
+        scoped_ptr<cc::AnimationCurve> curve) { }
 };
 
 } // namespace blink
 
 #endif // WebCompositorAnimationDelegate_h