CC Animation: Use ElementId to attach CC animation players.

cc/test/animation_timelines_test_common.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_TEST_ANIMATION_TIMELINES_TEST_COMMON_H_
 #define CC_TEST_ANIMATION_TIMELINES_TEST_COMMON_H_
 
 #include <memory>
 #include <unordered_map>
 
@@ skipping 209 matching lines @@
   void CreateTestImplLayer(ElementListType element_list_type);
 
   scoped_refptr<ElementAnimations> element_animations() const;
   scoped_refptr<ElementAnimations> element_animations_impl() const;
 
   void ReleaseRefPtrs();
 
   void AnimateLayersTransferEvents(base::TimeTicks time,
                                    unsigned expect_events);
 
-  AnimationPlayer* GetPlayerForLayerId(ElementId element_id);
-  AnimationPlayer* GetImplPlayerForLayerId(ElementId element_id);
+  AnimationPlayer* GetPlayerForElementId(ElementId element_id);
+  AnimationPlayer* GetImplPlayerForElementId(ElementId element_id);
 
-  int NextTestLayerId();
+  ElementId NextTestElementId();
 
   TestHostClient client_;
   TestHostClient client_impl_;
 
   AnimationHost* host_;
   AnimationHost* host_impl_;
 
   const int timeline_id_;
   const int player_id_;
   int element_id_;
 
-  int next_test_layer_id_;
+  ElementId next_test_element_id_;
 
   scoped_refptr<AnimationTimeline> timeline_;
   scoped_refptr<AnimationPlayer> player_;
 
   scoped_refptr<AnimationTimeline> timeline_impl_;
   scoped_refptr<AnimationPlayer> player_impl_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_ANIMATION_TIMELINES_TEST_COMMON_H_