cc: The SolidColorLayer should report contentsOpaque() true when its color is opaque

cc/solid_color_layer.h

 // Copyright 2012 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_SOLID_COLOR_LAYER_H_
 #define CC_SOLID_COLOR_LAYER_H_
 
 #include "cc/cc_export.h"
 #include "cc/layer.h"
 
 namespace cc {
 
 // A Layer that renders a solid color. The color is specified by using
 // setBackgroundColor() on the base class.
 class CC_EXPORT SolidColorLayer : public Layer {
 public:
     static scoped_refptr<SolidColorLayer> create();
 
     virtual scoped_ptr<LayerImpl> createLayerImpl() OVERRIDE;
 
+    virtual void setBackgroundColor(SkColor) OVERRIDE;
+
 protected:
     SolidColorLayer();
 
 private:
     virtual ~SolidColorLayer();
 };
 
 }
 #endif  // CC_SOLID_COLOR_LAYER_H_