Fix border radius on composited children.

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

 // Copyright 2014 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 PaintLayerPainter_h
 #define PaintLayerPainter_h
 
 #include "core/CoreExport.h"
 #include "core/paint/PaintLayerFragment.h"
 #include "core/paint/PaintLayerPaintingInfo.h"
@@ skipping 110 matching lines @@
                                           PaintLayerFlags);
 
   static bool needsToClip(const PaintLayerPaintingInfo& localPaintingInfo,
                           const ClipRect&);
 
   // Returns whether this layer should be painted during sofware painting (i.e.,
   // not via calls from CompositedLayerMapping to draw into composited layers).
   bool shouldPaintLayerInSoftwareMode(const GlobalPaintFlags,
                                       PaintLayerFlags paintFlags);
 
+  // Convert a fragmentOffset from the coordinate system of this painter's
+  // layer to the coordinate system of the layer in which it's border radius
+  // clip rect is defined, for painting composited children using mask layers.
+  LayoutPoint fragmentOffsetForAncestorClipMask(const LayoutPoint&);
+
   PaintLayer& m_paintLayer;
 };
 
 }  // namespace blink
 
 #endif  // PaintLayerPainter_h