cc : Stop pushing layers from hidden subtrees at commit

cc/trees/layer_tree_impl.h

Index: cc/trees/layer_tree_impl.h
diff --git a/cc/trees/layer_tree_impl.h b/cc/trees/layer_tree_impl.h
index 1d574938134bfda1011247e34ff89a55ea90ef01..28fb5eac182b5cc2a0aee779fd0770cba8359775 100644
--- a/cc/trees/layer_tree_impl.h
+++ b/cc/trees/layer_tree_impl.h
@@ -346,6 +346,11 @@ class CC_EXPORT LayerTreeImpl {
   void AddToElementMap(LayerImpl* layer);
   void RemoveFromElementMap(LayerImpl* layer);
 
+  using SurfaceIdsList = std::vector<const SurfaceId*>;
+  void SetHiddenSurfaceLayerIds(const SurfaceIdsList* hidden_surface_layer_ids);
+  const SurfaceIdsList* HiddenSurfaceLayerIds() const;
+  void ClearHiddenSurfaceLayerIds();
+
   void AddLayerShouldPushProperties(LayerImpl* layer);
   void RemoveLayerShouldPushProperties(LayerImpl* layer);
   std::unordered_set<LayerImpl*>& LayersThatShouldPushProperties();
@@ -579,6 +584,8 @@ class CC_EXPORT LayerTreeImpl {
   // is a pair of scrollbar layer ids instead of using a multimap.
   std::multimap<ElementId, int> element_id_to_scrollbar_layer_ids_;
 
+  SurfaceIdsList hidden_surface_layer_ids_;
+
   std::vector<PictureLayerImpl*> picture_layers_;
   LayerImplList surface_layers_;