Large canvas does not honor containing div's border radius

Source/core/rendering/PaintPhase.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 31 matching lines @@
     PaintPhaseChildBlockBackground,
     PaintPhaseChildBlockBackgrounds,
     PaintPhaseFloat,
     PaintPhaseForeground,
     PaintPhaseOutline,
     PaintPhaseChildOutlines,
     PaintPhaseSelfOutline,
     PaintPhaseSelection,
     PaintPhaseCollapsedTableBorders,
     PaintPhaseTextClip,
-    PaintPhaseMask
+    PaintPhaseMask,
+    PaintPhaseClippingMask,
 };
 
 enum PaintBehaviorFlags {
     PaintBehaviorNormal = 0,
     PaintBehaviorSelectionOnly = 1 << 0,
     PaintBehaviorForceBlackText = 1 << 1,
     PaintBehaviorFlattenCompositingLayers = 1 << 2,
     PaintBehaviorRenderingSVGMask = 1 << 3,
     PaintBehaviorSkipRootBackground = 1 << 4,
     PaintBehaviorRootBackgroundOnly = 1 << 5
 };
 
 typedef unsigned PaintBehavior;
 
 } // namespace WebCore
 
 #endif // PaintPhase_h