cc : Update render surfaces using LayerListIterator instead of treewalk

cc/test/layer_tree_host_common_test.cc

 // Copyright 2014 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/test/layer_tree_host_common_test.h"
 
 #include <stddef.h>
 
 #include "cc/layers/layer.h"
 #include "cc/layers/layer_impl.h"
@@ skipping 149 matching lines @@
 }
 
 void LayerTreeHostCommonTestBase::ExecuteCalculateDrawProperties(
     LayerImpl* root_layer,
     float device_scale_factor,
     float page_scale_factor,
     LayerImpl* page_scale_layer,
     bool can_use_lcd_text,
     bool layers_always_allowed_lcd_text) {
   host_impl()->active_tree()->SetDeviceScaleFactor(device_scale_factor);
-  host_impl()->active_tree()->SetPageScaleOnActiveTree(page_scale_factor);
+  if (host_impl()->active_tree()->property_trees()->needs_rebuild)

[ajuma, 2016/03/22 14:41:54]

Why does this depend on whether we need to rebuild?

[jaydasika, 2016/03/22 20:48:34]

Whoops, it should be the other way around, if we are going to build property
trees, we don't need to update page scale factor as property tree builder will
take care of it. Will remove this anyway as there is  no harm in doing it twice.

+    host_impl()->active_tree()->SetPageScaleOnActiveTree(page_scale_factor);
 
   gfx::Transform identity_matrix;
   gfx::Size device_viewport_size =
       gfx::Size(root_layer->bounds().width() * device_scale_factor,
                 root_layer->bounds().height() * device_scale_factor);
 
   render_surface_layer_list_impl_.reset(new LayerImplList);
 
   // We are probably not testing what is intended if the root_layer bounds are
   // empty.
@@ skipping 47 matching lines @@
 
 LayerTreeHostCommonTest::LayerTreeHostCommonTest()
     : LayerTreeHostCommonTestBase(LayerTreeSettings()) {}
 
 LayerTreeHostCommonTest::LayerTreeHostCommonTest(
     const LayerTreeSettings& settings)
     : LayerTreeHostCommonTestBase(settings) {
 }
 
 }  // namespace cc