CC Animation: Make ElementAnimations a ref-counted object.

cc/animation/animation_player.h

 // Copyright 2015 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 CC_ANIMATION_ANIMATION_PLAYER_H_
 #define CC_ANIMATION_ANIMATION_PLAYER_H_
 
 #include <vector>
 
 #include "base/containers/linked_list.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "cc/animation/animation.h"
 #include "cc/animation/animation_curve.h"
+#include "cc/animation/element_animations.h"
 #include "cc/base/cc_export.h"
 
 namespace cc {
 
 class AnimationDelegate;
 class AnimationHost;
 class AnimationTimeline;
 class ElementAnimations;
 class LayerAnimationController;
 enum class LayerTreeType;
@@ skipping 23 matching lines @@
   void SetAnimationHost(AnimationHost* animation_host);
 
   // Parent AnimationTimeline.
   AnimationTimeline* animation_timeline() { return animation_timeline_; }
   const AnimationTimeline* animation_timeline() const {
     return animation_timeline_;
   }
   void SetAnimationTimeline(AnimationTimeline* timeline);
 
   // ElementAnimations object where this player is listed.
-  // ElementAnimations has a reference to shared LayerAnimationController.
-  ElementAnimations* element_animations() const { return element_animations_; }
+  scoped_refptr<ElementAnimations> element_animations() const {
+    return element_animations_;
+  }
 
   void set_layer_animation_delegate(AnimationDelegate* delegate) {
     layer_animation_delegate_ = delegate;
   }
 
   void AttachLayer(int layer_id);
   void DetachLayer();
 
   void AddAnimation(std::unique_ptr<Animation> animation);
   void PauseAnimation(int animation_id, double time_offset);
@@ skipping 39 matching lines @@
   void UnbindElementAnimations();
 
   // We accumulate added animations in animations_ container
   // if element_animations_ is a nullptr. It allows us to add/remove animations
   // to non-attached AnimationPlayers.
   std::vector<std::unique_ptr<Animation>> animations_;
 
   AnimationHost* animation_host_;
   AnimationTimeline* animation_timeline_;
   // element_animations isn't null if player attached to an element (layer).
-  ElementAnimations* element_animations_;
+  scoped_refptr<ElementAnimations> element_animations_;
   AnimationDelegate* layer_animation_delegate_;
 
   int id_;
   int layer_id_;
 
   DISALLOW_COPY_AND_ASSIGN(AnimationPlayer);
 };
 
 }  // namespace cc
 
 #endif  // CC_ANIMATION_ANIMATION_PLAYER_H_