cc : Push layer lists instead of layer tree at commit and activation

cc/layers/picture_layer_unittest.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 "cc/layers/picture_layer.h"
 
 #include <stddef.h>
 
 #include "base/memory/ptr_util.h"
 #include "base/threading/thread_task_runner_handle.h"
@@ skipping 322 matching lines @@
   layer_tree_settings.image_decode_tasks_enabled = true;
   FakeLayerTreeHostImpl host_impl(layer_tree_settings,
                                   &impl_task_runner_provider,
                                   &shared_bitmap_manager, &task_graph_runner);
   host_impl.SetVisible(true);
   EXPECT_TRUE(host_impl.InitializeRenderer(output_surface.get()));
 
   host_impl.CreatePendingTree();
   host_impl.pending_tree()->SetRootLayer(
       FakePictureLayerImpl::Create(host_impl.pending_tree(), 1));
+  host_impl.pending_tree()->BuildLayerListForTesting();
 
   FakePictureLayerImpl* layer_impl = static_cast<FakePictureLayerImpl*>(
       host_impl.pending_tree()->root_layer());
 
   layer->PushPropertiesTo(layer_impl);
 
   host->CommitComplete();
   EXPECT_EQ(2, host->source_frame_number());
 
   host_impl.ActivateSyncTree();
@@ skipping 125 matching lines @@
   // Do a main frame, record the picture layers. The frame number has changed
   // non-monotonically.
   layer->SetNeedsDisplay();
   host2->Composite(base::TimeTicks::Now());
   EXPECT_EQ(3, layer->update_count());
   EXPECT_EQ(1, host2->source_frame_number());
 }
 
 }  // namespace
 }  // namespace cc