Deduplicating compositing scrollingCoordinator helper

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.h

 /*
  * Copyright (C) 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 286 matching lines @@
   // opaque this allows us to composite the scroller even on low DPI as we can
   // draw with subpixel anti-aliasing.
   bool backgroundPaintsOntoScrollingContentsLayer() {
     return m_backgroundPaintsOntoScrollingContentsLayer;
   }
 
   bool drawsBackgroundOntoContentLayer() {
     return m_drawsBackgroundOntoContentLayer;
   }
 
+  static ScrollingCoordinator* scrollingCoordinatorFromLayer(PaintLayer&);
+
  private:
   IntRect recomputeInterestRect(const GraphicsLayer*) const;
   static bool interestRectChangedEnoughToRepaint(
       const IntRect& previousInterestRect,
       const IntRect& newInterestRect,
       const IntSize& layerSize);
 
   static const GraphicsLayerPaintInfo* containingSquashedLayer(
       const LayoutObject*,
       const Vector<GraphicsLayerPaintInfo>& layers,
@@ skipping 387 matching lines @@
   unsigned m_backgroundPaintsOntoGraphicsLayer : 1;
 
   bool m_drawsBackgroundOntoContentLayer;
 
   friend class CompositedLayerMappingTest;
 };
 
 }  // namespace blink
 
 #endif  // CompositedLayerMapping_h