cc : Stop calculating visible rects on main thread

cc/trees/property_tree_builder.h

 // 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.
 
 #ifndef CC_TREES_PROPERTY_TREE_BUILDER_H_
 #define CC_TREES_PROPERTY_TREE_BUILDER_H_
 
 #include <vector>
 
 #include "cc/trees/layer_tree_host_common.h"
 #include "cc/trees/property_tree.h"
 
 namespace cc {
 
 class LayerTreeHost;
 
 class PropertyTreeBuilder {
  public:
-  static void BuildPropertyTrees(Layer* root_layer,
-                                 const Layer* page_scale_layer,
-                                 const Layer* inner_viewport_scroll_layer,
-                                 const Layer* outer_viewport_scroll_layer,
-                                 const Layer* overscroll_elasticity_layer,
-                                 const gfx::Vector2dF& elastic_overscroll,
-                                 float page_scale_factor,
-                                 float device_scale_factor,
-                                 const gfx::Rect& viewport,
-                                 const gfx::Transform& device_transform,
-                                 PropertyTrees* property_trees);
+  static void CC_EXPORT
+  BuildPropertyTrees(Layer* root_layer,
+                     const Layer* page_scale_layer,
+                     const Layer* inner_viewport_scroll_layer,
+                     const Layer* outer_viewport_scroll_layer,
+                     const Layer* overscroll_elasticity_layer,
+                     const gfx::Vector2dF& elastic_overscroll,
+                     float page_scale_factor,
+                     float device_scale_factor,
+                     const gfx::Rect& viewport,
+                     const gfx::Transform& device_transform,
+                     PropertyTrees* property_trees);
   static void BuildPropertyTrees(LayerImpl* root_layer,
                                  const LayerImpl* page_scale_layer,
                                  const LayerImpl* inner_viewport_scroll_layer,
                                  const LayerImpl* outer_viewport_scroll_layer,
                                  const LayerImpl* overscroll_elasticity_layer,
                                  const gfx::Vector2dF& elastic_overscroll,
                                  float page_scale_factor,
                                  float device_scale_factor,
                                  const gfx::Rect& viewport,
                                  const gfx::Transform& device_transform,
                                  PropertyTrees* property_trees);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_PROPERTY_TREE_BUILDER_H_