Keeping track of descendants that draw content instead of recalcualting

cc/layers/texture_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_TEXTURE_LAYER_H_
 #define CC_LAYERS_TEXTURE_LAYER_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 116 matching lines @@
 
   // Use this for special cases where the same texture is used to back the
   // TextureLayer across all frames.
   // WARNING: DON'T ACTUALLY USE THIS WHAT YOU ARE DOING IS WRONG.
   // TODO(danakj): Remove this when pepper doesn't need it. crbug.com/350204
   void SetTextureMailboxWithoutReleaseCallback(const TextureMailbox& mailbox);
 
   virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect) OVERRIDE;
 
   virtual void SetLayerTreeHost(LayerTreeHost* layer_tree_host) OVERRIDE;
-  virtual bool DrawsContent() const OVERRIDE;
   virtual bool Update(ResourceUpdateQueue* queue,
                       const OcclusionTracker<Layer>* occlusion) OVERRIDE;
   virtual void PushPropertiesTo(LayerImpl* layer) OVERRIDE;
   virtual Region VisibleContentOpaqueRegion() const OVERRIDE;
 
  protected:
   explicit TextureLayer(TextureLayerClient* client);
   virtual ~TextureLayer();
+  virtual bool HasDrawableContent() const OVERRIDE;
 
  private:
   void SetTextureMailboxInternal(
       const TextureMailbox& mailbox,
       scoped_ptr<SingleReleaseCallback> release_callback,
       bool requires_commit,
       bool allow_mailbox_reuse);
 
   TextureLayerClient* client_;
 
   bool flipped_;
   gfx::PointF uv_top_left_;
   gfx::PointF uv_bottom_right_;
   // [bottom left, top left, top right, bottom right]
   float vertex_opacity_[4];
   bool premultiplied_alpha_;
   bool blend_background_color_;
   bool rate_limit_context_;
 
   scoped_ptr<TextureMailboxHolder::MainThreadReference> holder_ref_;
   bool needs_set_mailbox_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureLayer);
 };
 
 }  // namespace cc
 #endif  // CC_LAYERS_TEXTURE_LAYER_H_