cc: Make LayerTreeHost a protected Layer member.

cc/trees/layer_tree_host_unittest_serialization.cc

 // 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.
 
 #include "cc/trees/layer_tree_host.h"
 
 #include <memory>
 
 #include "base/memory/ptr_util.h"
 #include "cc/layers/empty_content_layer_client.h"
@@ skipping 75 matching lines @@
     layer_tree_host_dst_->GetLayerTree()->in_paint_layer_contents_ = false;
 
     // Need to reset LayerTreeHost pointers before tear down.
     layer_tree_host_src_ = nullptr;
     layer_tree_host_dst_ = nullptr;
   }
 
   void VerifyHostHasAllExpectedLayersInTree(Layer* root_layer) {
     LayerTreeHostCommon::CallFunctionForEveryLayer(
         root_layer->GetLayerTree(), [root_layer](Layer* layer) {
-          DCHECK(layer->layer_tree_host());
+          DCHECK(layer->GetLayerTreeHostForTesting());
           EXPECT_EQ(layer, layer->GetLayerTree()->LayerById(layer->id()));
         });
   }
 
   void VerifySerializationAndDeserialization() {
     proto::LayerTreeHost proto;
     LayerTree* layer_tree_src = layer_tree_host_src_->GetLayerTree();
     LayerTree* layer_tree_dst = layer_tree_host_dst_->GetLayerTree();
 
     std::unordered_set<Layer*> layers_that_should_push_properties_src =
         layer_tree_src->LayersThatShouldPushProperties();
     std::vector<std::unique_ptr<SwapPromise>> swap_promises;
     layer_tree_host_src_->ToProtobufForCommit(&proto, &swap_promises);
     layer_tree_host_dst_->FromProtobufForCommit(proto);
 
     EXPECT_EQ(layer_tree_src->needs_full_tree_sync_,
               layer_tree_dst->needs_full_tree_sync_);
     EXPECT_EQ(layer_tree_src->needs_meta_info_recomputation_,
               layer_tree_dst->needs_meta_info_recomputation_);
     EXPECT_EQ(layer_tree_host_src_->source_frame_number_,
               layer_tree_host_dst_->source_frame_number_);
     EXPECT_EQ(layer_tree_host_src_->root_layer()->id(),
               layer_tree_host_dst_->root_layer()->id());
     EXPECT_EQ(layer_tree_host_dst_.get(),
-              layer_tree_dst->inputs_.root_layer->layer_tree_host());
+              layer_tree_dst->inputs_.root_layer->GetLayerTreeHostForTesting());
     EXPECT_EQ(layer_tree_src->inputs_.root_layer->double_sided(),
               layer_tree_dst->inputs_.root_layer->double_sided());
     EXPECT_EQ(
         layer_tree_host_src_->debug_state_.show_replica_screen_space_rects,
         layer_tree_host_dst_->debug_state_.show_replica_screen_space_rects);
     EXPECT_EQ(layer_tree_src->inputs_.device_viewport_size,
               layer_tree_dst->inputs_.device_viewport_size);
     EXPECT_EQ(layer_tree_src->inputs_.top_controls_shrink_blink_size,
               layer_tree_dst->inputs_.top_controls_shrink_blink_size);
     EXPECT_EQ(layer_tree_src->inputs_.top_controls_height,
@@ skipping 322 matching lines @@
 
 TEST_F(LayerTreeHostSerializationTest, AddAndRemoveNodeFromLayerTree) {
   RunAddAndRemoveNodeFromLayerTree();
 }
 
 TEST_F(LayerTreeHostSerializationTest, PictureLayerMultipleSerializations) {
   RunPictureLayerMultipleSerializationsTest();
 }
 
 }  // namespace cc