Revert of Use element id's for animations

cc/animation/animation_host_perftest.cc

 // Copyright 2016 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.
 
 #include "cc/animation/animation_host.h"
 
 #include "base/threading/thread_task_runner_handle.h"
 #include "cc/animation/animation_id_provider.h"
 #include "cc/animation/animation_player.h"
 #include "cc/animation/animation_timeline.h"
@@ skipping 44 matching lines @@
     scoped_refptr<AnimationTimeline> timeline =
         AnimationTimeline::Create(AnimationIdProvider::NextTimelineId());
     host()->AddAnimationTimeline(timeline);
 
     const int first_player_id = AnimationIdProvider::NextPlayerId();
     int last_player_id = first_player_id;
 
     for (int i = 0; i < num_players; ++i) {
       scoped_refptr<Layer> layer = Layer::Create();
       root_layer_->AddChild(layer);
-      layer->SetElementId(LayerIdToElementIdForTesting(layer->id()));
 
       scoped_refptr<AnimationPlayer> player =
           AnimationPlayer::Create(last_player_id);
       last_player_id = AnimationIdProvider::NextPlayerId();
 
       timeline->AttachPlayer(player);
-      player->AttachElement(layer->element_id());
+      player->AttachElement(layer->id());
       EXPECT_TRUE(player->element_animations());
     }
 
     // Create impl players.
     layer_tree_host_->CommitAndCreateLayerImplTree();
 
     // Check impl instances created.
     scoped_refptr<AnimationTimeline> timeline_impl =
         host_impl()->GetTimelineById(timeline->id());
     EXPECT_TRUE(timeline_impl);
@@ skipping 50 matching lines @@
   CreateTimelines(10);
   DoTest();
 }
 
 TEST_F(AnimationHostPerfTest, Push1000TimelinesPropertiesTo) {
   CreateTimelines(1000);
   DoTest();
 }
 
 }  // namespace cc