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

cc/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_LAYER_H_
 #define CC_LAYER_H_
 
 #include "Region.h"
 #include "base/memory/ref_counted.h"
 #include "cc/cc_export.h"
@@ skipping 56 matching lines @@
     void setChildren(const LayerList&);
 
     const LayerList& children() const { return m_children; }
 
     void setAnchorPoint(const gfx::PointF&);
     gfx::PointF anchorPoint() const { return m_anchorPoint; }
 
     void setAnchorPointZ(float);
     float anchorPointZ() const { return m_anchorPointZ; }
 
-    void setBackgroundColor(SkColor);
+    virtual void setBackgroundColor(SkColor);
     SkColor backgroundColor() const { return m_backgroundColor; }
 
     // A layer's bounds are in logical, non-page-scaled pixels (however, the
     // root layer's bounds are in physical pixels).
     void setBounds(const gfx::Size&);
     const gfx::Size& bounds() const { return m_bounds; }
     virtual gfx::Size contentBounds() const;
 
     void setMasksToBounds(bool);
     bool masksToBounds() const { return m_masksToBounds; }
@@ skipping 319 matching lines @@
 
     WebKit::WebAnimationDelegate* m_layerAnimationDelegate;
     WebKit::WebLayerScrollClient* m_layerScrollClient;
 };
 
 void sortLayers(std::vector<scoped_refptr<Layer> >::iterator, std::vector<scoped_refptr<Layer> >::iterator, void*);
 
 }  // namespace cc
 
 #endif  // CC_LAYER_H_