[CSS Regions] Elements in a region should be assignable to a named flow

Source/core/rendering/RenderRegion.h

 /*
  * Copyright (C) 2011 Adobe Systems Incorporated. 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.
@@ skipping 127 matching lines @@
     LayoutRect overflowRectForFlowThreadPortion(LayoutRect flowThreadPortionRect, bool isFirstPortion, bool isLastPortion) const;
     void repaintFlowThreadContentRectangle(const LayoutRect& repaintRect, const LayoutRect& flowThreadPortionRect,
         const LayoutRect& flowThreadPortionOverflowRect, const LayoutPoint& regionLocation) const;
 
     virtual bool shouldHaveAutoLogicalHeight() const;
 
 private:
     virtual const char* renderName() const { return "RenderRegion"; }
 
     virtual bool canHaveChildren() const OVERRIDE { return false; }
+    virtual bool canDOMChildrenHaveRenderParent() const OVERRIDE { return true; }
 
     virtual void insertedIntoTree() OVERRIDE;
     virtual void willBeRemovedFromTree() OVERRIDE;
 
     virtual void layoutBlock(bool relayoutChildren, LayoutUnit pageLogicalHeight = 0) OVERRIDE;
     virtual void paintObject(PaintInfo&, const LayoutPoint&) OVERRIDE;
 
     virtual void installFlowThread();
 
     PassRefPtr<RenderStyle> computeStyleInRegion(const RenderObject*);
@@ skipping 53 matching lines @@
     ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isRenderRegion());
     return static_cast<const RenderRegion*>(object);
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toRenderRegion(const RenderRegion*);
 
 } // namespace WebCore
 
 #endif // RenderRegion_h