cc : Stop pushing layers from hidden subtrees at commit

cc/trees/layer_tree_host.h

Index: cc/trees/layer_tree_host.h
diff --git a/cc/trees/layer_tree_host.h b/cc/trees/layer_tree_host.h
index 7456229a49ea709f818c8ef4d16d39eae23e70fe..f69c6d6121a5cb14f56b9e6428dbb06dd248dcd3 100644
--- a/cc/trees/layer_tree_host.h
+++ b/cc/trees/layer_tree_host.h
@@ -352,6 +352,11 @@ class CC_EXPORT LayerTreeHost : public NON_EXPORTED_BASE(SurfaceReferenceOwner),
   void SetHasCopyRequest(bool has_copy_request);
   bool has_copy_request() const { return has_copy_request_; }
 
+  using SurfaceIdsList = std::vector<const SurfaceId*>;
+  void AddHiddenSurfaceLayerId(Layer* layer);
+  const SurfaceIdsList* HiddenSurfaceLayerIds() const;
+  void ClearHiddenSurfaceLayerIds();
+
   void AddLayerShouldPushProperties(Layer* layer);
   void RemoveLayerShouldPushProperties(Layer* layer);
   std::unordered_set<Layer*>& LayersThatShouldPushProperties();
@@ -616,6 +621,8 @@ class CC_EXPORT LayerTreeHost : public NON_EXPORTED_BASE(SurfaceReferenceOwner),
 
   scoped_refptr<HeadsUpDisplayLayer> hud_layer_;
 
+  SurfaceIdsList hidden_surface_layer_ids_;
+
   // Set of layers that need to push properties.
   std::unordered_set<Layer*> layers_that_should_push_properties_;