Support high DPI scrollbar on top level web frame.

cc/LayerChromium.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 LayerChromium_h
 #define LayerChromium_h
 
 #if USE(ACCELERATED_COMPOSITING)
 
@@ skipping 246 matching lines @@
     virtual ScrollbarLayerChromium* toScrollbarLayerChromium() { return 0; }
 
 protected:
     friend class CCLayerImpl;
     friend class TreeSynchronizer;
 
     LayerChromium();
 
     void setNeedsCommit();
 
+    IntRect layerRectToContentRect(const WebKit::WebRect& layerRect);
+
     // This flag is set when layer need repainting/updating.
     bool m_needsDisplay;
 
     // Tracks whether this layer may have changed stacking order with its siblings.
     bool m_stackingOrderChanged;
 
     // The update rect is the region of the compositor resource that was actually updated by the compositor.
     // For layers that may do updating outside the compositor's control (i.e. plugin layers), this information
     // is not available and the update rect will remain empty.
     // Note this rect is in layer space (not content space).
@@ skipping 89 matching lines @@
     WebKit::WebAnimationDelegate* m_layerAnimationDelegate;
     WebKit::WebLayerScrollClient* m_layerScrollClient;
 };
 
 void sortLayers(Vector<RefPtr<LayerChromium> >::iterator, Vector<RefPtr<LayerChromium> >::iterator, void*);
 
 }
 #endif // USE(ACCELERATED_COMPOSITING)
 
 #endif