cc : Make CallFunctionForSubtree on impl use layer iterator

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 "cc/layers/heads_up_display_layer.h"
 #include "cc/layers/layer.h"
 #include "cc/proto/layer.pb.h"
 #include "cc/proto/layer_tree_host.pb.h"
@@ skipping 28 matching lines @@
     // Need to reset |in_paint_layer_contents_| to tear down.
     layer_tree_host_src_->in_paint_layer_contents_ = false;
     layer_tree_host_dst_->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::CallFunctionForSubtree(
-        root_layer, [root_layer](Layer* layer) {
+    LayerTreeHostCommon::CallFunctionForEveryLayer(
+        root_layer->layer_tree_host(), [root_layer](Layer* layer) {
           DCHECK(layer->layer_tree_host());
           EXPECT_EQ(layer, layer->layer_tree_host()->LayerById(layer->id()));
         });
   }
 
   void VerifySerializationAndDeserialization() {
     proto::LayerTreeHost proto;
 
     std::unordered_set<Layer*> layers_that_should_push_properties_src =
         layer_tree_host_src_->LayersThatShouldPushProperties();
@@ skipping 103 matching lines @@
     EXPECT_EQ(layer_tree_host_src_->property_trees_,
               layer_tree_host_dst_->property_trees_);
     EXPECT_EQ(layer_tree_host_src_->surface_id_namespace_,
               layer_tree_host_dst_->surface_id_namespace_);
     EXPECT_EQ(layer_tree_host_src_->next_surface_sequence_,
               layer_tree_host_dst_->next_surface_sequence_);
 
     // All layers must have a property tree index that matches PropertyTrees.
     if (layer_tree_host_dst_->property_trees_.sequence_number) {
       int seq_num = layer_tree_host_dst_->property_trees_.sequence_number;
-      LayerTreeHostCommon::CallFunctionForSubtree(
-          layer_tree_host_dst_->root_layer_.get(), [seq_num](Layer* layer) {
+      LayerTreeHostCommon::CallFunctionForEveryLayer(
+          layer_tree_host_dst_.get(), [seq_num](Layer* layer) {
             EXPECT_EQ(seq_num, layer->property_tree_sequence_number());
           });
     }
   }
 
   void RunAllMembersChangedTest() {
     layer_tree_host_src_->needs_full_tree_sync_ =
         !layer_tree_host_src_->needs_full_tree_sync_;
     layer_tree_host_src_->needs_meta_info_recomputation_ =
         !layer_tree_host_src_->needs_meta_info_recomputation_;
@@ skipping 180 matching lines @@
 
 TEST_F(LayerTreeHostSerializationTest, LayersChangedMultipleSerializations) {
   RunLayersChangedMultipleSerializations();
 }
 
 TEST_F(LayerTreeHostSerializationTest, AddAndRemoveNodeFromLayerTree) {
   RunAddAndRemoveNodeFromLayerTree();
 }
 
 }  // namespace cc