Deduplicating compositing scrollingCoordinator helper

third_party/WebKit/Source/core/paint/PaintLayer.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
@@ skipping 554 matching lines @@
       const LayoutObject&,
       const LayoutBoxModelObject& paint_invalidation_container,
       LayoutRect&);
 
   bool PaintsWithTransparency(GlobalPaintFlags global_paint_flags) const {
     return IsTransparent() &&
            ((global_paint_flags & kGlobalPaintFlattenCompositingLayers) ||
             GetCompositingState() != kPaintsIntoOwnBacking);
   }
 
+  // Returns the ScrollingCoordinator associated with this layer, if
+  // any. Otherwise nullptr.
+  ScrollingCoordinator* GetScrollingCoordinator();
+
   // Returns true if the element or any ancestor is transformed.
   bool CompositesWithTransform() const;
 
   // Returns true if the element or any ancestor has non 1 opacity.
   bool CompositesWithOpacity() const;
 
   bool PaintsWithTransform(GlobalPaintFlags) const;
 
   // Returns true if background phase is painted opaque in the given rect.
   // The query rect is given in local coordinates.
@@ skipping 683 matching lines @@
 
 }  // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 CORE_EXPORT void showLayerTree(const blink::PaintLayer*);
 CORE_EXPORT void showLayerTree(const blink::LayoutObject*);
 #endif
 
 #endif  // Layer_h