[cc] Store CCLayerImpls as scoped_ptrs

cc/SolidColorLayerChromium.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 SolidColorLayerChromium_h
 #define SolidColorLayerChromium_h
 
 #if USE(ACCELERATED_COMPOSITING)
 
 #include "LayerChromium.h"
 
 namespace cc {
 
 // A Layer that renders a solid color. The color is specified by using
 // setBackgroundColor() on the base class.
 class SolidColorLayerChromium : public LayerChromium {
 public:
     static scoped_refptr<SolidColorLayerChromium> create();
 
-    virtual PassOwnPtr<CCLayerImpl> createCCLayerImpl() OVERRIDE;
+    virtual scoped_ptr<CCLayerImpl> createCCLayerImpl() OVERRIDE;
 
 protected:
     SolidColorLayerChromium();
 
 private:
     virtual ~SolidColorLayerChromium();
 };
 
 }
 #endif // USE(ACCELERATED_COMPOSITING)
 
 #endif