cc : Stop pushing layers from hidden subtrees at commit

cc/layers/layer.h

 // Copyright 2010 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_LAYERS_LAYER_H_
 #define CC_LAYERS_LAYER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 359 matching lines @@
   void set_should_flatten_transform_from_property_tree(bool should_flatten) {
     if (should_flatten_transform_from_property_tree_ == should_flatten)
       return;
     should_flatten_transform_from_property_tree_ = should_flatten;
     SetNeedsPushProperties();
   }
   bool should_flatten_transform_from_property_tree() const {
     return should_flatten_transform_from_property_tree_;
   }
 
+  void SetIsHidden(bool is_hidden);
+
+  bool is_hidden() const { return is_hidden_; }
+
   const gfx::Rect& visible_layer_rect_for_testing() const {
     return visible_layer_rect_;
   }
   void set_visible_layer_rect(const gfx::Rect& rect) {
     visible_layer_rect_ = rect;
   }
 
   // This is for tracking damage.
   void SetSubtreePropertyChanged();
   bool subtree_property_changed() const { return subtree_property_changed_; }
@@ skipping 216 matching lines @@
 
   int num_descendants_that_draw_content_;
   int transform_tree_index_;
   int effect_tree_index_;
   int clip_tree_index_;
   int scroll_tree_index_;
   int property_tree_sequence_number_;
   gfx::Vector2dF offset_to_transform_parent_;
   bool should_flatten_transform_from_property_tree_ : 1;
   bool draws_content_ : 1;
+  bool is_hidden_ : 1;
   bool use_local_transform_for_backface_visibility_ : 1;
   bool should_check_backface_visibility_ : 1;
   bool force_render_surface_for_testing_ : 1;
   bool subtree_property_changed_ : 1;
   bool may_contain_video_ : 1;
   bool is_scroll_clip_layer_ : 1;
   bool needs_show_scrollbars_ : 1;
   // This value is valid only when LayerTreeHost::has_copy_request() is true
   bool subtree_has_copy_request_ : 1;
   SkColor safe_opaque_background_color_;
   std::unique_ptr<std::set<Layer*>> scroll_children_;
 
   std::unique_ptr<std::set<Layer*>> clip_children_;
 
   // These all act like draw properties, so don't need push properties.
   gfx::Rect visible_layer_rect_;
   size_t num_unclipped_descendants_;
 
   DISALLOW_COPY_AND_ASSIGN(Layer);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_H_