Introduce composed tree version of rightPositionOf()

Source/core/editing/VisibleUnits.h

 /*
  * Copyright (C) 2004 Apple Computer, 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 83 matching lines @@
 
 CORE_EXPORT UChar32 characterAfter(const VisiblePosition&);
 CORE_EXPORT UChar32 characterAfter(const VisiblePositionInComposedTree&);
 UChar32 characterBefore(const VisiblePosition&);
 
 // TODO(yosin) Since return value of |leftPositionOf()| with |VisiblePosition|
 // isn't defined well on composed tree, we should not use it for a position in
 // composed tree.
 CORE_EXPORT VisiblePosition leftPositionOf(const VisiblePosition&);
 CORE_EXPORT VisiblePositionInComposedTree leftPositionOf(const VisiblePositionInComposedTree&);
-VisiblePosition rightPositionOf(const VisiblePosition&);
+// TODO(yosin) Since return value of |rightPositionOf()| with |VisiblePosition|
+// isn't defined well on composed tree, we should not use it for a position in
+// composed tree.
+CORE_EXPORT VisiblePosition rightPositionOf(const VisiblePosition&);
+CORE_EXPORT VisiblePositionInComposedTree rightPositionOf(const VisiblePositionInComposedTree&);
 
 CORE_EXPORT VisiblePosition nextPositionOf(const VisiblePosition&, EditingBoundaryCrossingRule = CanCrossEditingBoundary);
 CORE_EXPORT VisiblePositionInComposedTree nextPositionOf(const VisiblePositionInComposedTree&, EditingBoundaryCrossingRule = CanCrossEditingBoundary);
 VisiblePosition previousPositionOf(const VisiblePosition&, EditingBoundaryCrossingRule = CanCrossEditingBoundary);
 
 // words
 CORE_EXPORT VisiblePosition startOfWord(const VisiblePosition&, EWordSide = RightWordIfOnBoundary);
 CORE_EXPORT VisiblePosition endOfWord(const VisiblePosition&, EWordSide = RightWordIfOnBoundary);
 VisiblePosition previousWordPosition(const VisiblePosition&);
 VisiblePosition nextWordPosition(const VisiblePosition&);
@@ skipping 68 matching lines @@
 
 // Returns a hit-tested VisiblePosition for the given point in contents-space
 // coordinates.
 CORE_EXPORT VisiblePosition visiblePositionForContentsPoint(const IntPoint&, LocalFrame*);
 
 CORE_EXPORT bool rendersInDifferentPosition(const Position&, const Position&);
 
 } // namespace blink
 
 #endif // VisibleUnits_h