Transfer LayerImpl ownership to LayerTreeImpl

cc/tiles/tile_manager_perftest.cc

 // Copyright 2013 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 <stddef.h>
 #include <stdint.h>
 
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/thread_task_runner_handle.h"
@@ skipping 146 matching lines @@
                   scoped_refptr<DisplayListRasterSource> active_raster_source) {
     SetupPendingTree(active_raster_source);
     ActivateTree();
     SetupPendingTree(pending_raster_source);
   }
 
   void SetupPendingTree(scoped_refptr<DisplayListRasterSource> raster_source) {
     host_impl_.CreatePendingTree();
     LayerTreeImpl* pending_tree = host_impl_.pending_tree();
     // Clear recycled tree.
-    pending_tree->DetachLayerTree();
+    pending_tree->ClearLayers();
 
     scoped_ptr<FakePictureLayerImpl> pending_layer =
         FakePictureLayerImpl::CreateWithRasterSource(pending_tree, id_,
                                                      raster_source);
     pending_layer->SetDrawsContent(true);
     pending_layer->SetForceRenderSurface(true);
     pending_tree->SetRootLayer(std::move(pending_layer));
     pending_tree->BuildPropertyTreesForTesting();
 
     pending_root_layer_ = static_cast<FakePictureLayerImpl*>(
@@ skipping 296 matching lines @@
   RunEvictionQueueConstructAndIterateTest("10_64", 10, 64);
   RunEvictionQueueConstructAndIterateTest("10_128", 10, 128);
   RunEvictionQueueConstructAndIterateTest("50_16", 50, 16);
   RunEvictionQueueConstructAndIterateTest("50_32", 50, 32);
   RunEvictionQueueConstructAndIterateTest("50_64", 50, 64);
   RunEvictionQueueConstructAndIterateTest("50_128", 50, 128);
 }
 
 }  // namespace
 }  // namespace cc