Add flag for drawing layers to screen with Ganesh

cc/layers/layer_impl.h

 // Copyright 2011 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_IMPL_H_
 #define CC_LAYERS_LAYER_IMPL_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 418 matching lines @@
 
   virtual void AsValueInto(base::DictionaryValue* dict) const;
 
   void NoteLayerSurfacePropertyChanged();
   void NoteLayerPropertyChanged();
   void NoteLayerPropertyChangedForSubtree();
 
   // Note carefully this does not affect the current layer.
   void NoteLayerPropertyChangedForDescendants();
 
+  bool CanDrawDirectlyToBackbuffer() const;
+
  private:
   void UpdateScrollbarPositions();
 
   virtual const char* LayerTypeAsString() const;
 
   void DumpLayer(std::string* str, int indent) const;
 
   // Properties internal to LayerImpl
   LayerImpl* parent_;
   OwnedLayerImplList children_;
@@ skipping 95 matching lines @@
   // Group of properties that need to be computed based on the layer tree
   // hierarchy before layers can be drawn.
   DrawProperties<LayerImpl, RenderSurfaceImpl> draw_properties_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_IMPL_H_