Oilpan: Move CSSStyleDeclaration and subclasses to the heap using transistion types.

Source/core/dom/Position.h

 /*
  * Copyright (C) 2004, 2006, 2008 Apple 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 127 matching lines @@
     // These should only be used for PositionIsOffsetInAnchor positions, unless
     // the position is a legacy editing position.
     void moveToPosition(PassRefPtr<Node> anchorNode, int offset);
     void moveToOffset(int offset);
 
     bool isNull() const { return !m_anchorNode; }
     bool isNotNull() const { return m_anchorNode; }
     bool isOrphan() const { return m_anchorNode && !m_anchorNode->inDocument(); }
 
     Element* element() const;
-    PassRefPtr<CSSComputedStyleDeclaration> computedStyle() const;
+    PassRefPtrWillBeRawPtr<CSSComputedStyleDeclaration> computedStyle() const;
 
     // Move up or down the DOM by one position.
     // Offsets are computed using render text for nodes that have renderers - but note that even when
     // using composed characters, the result may be inside a single user-visible character if a ligature is formed.
     Position previous(PositionMoveType = CodePoint) const;
     Position next(PositionMoveType = CodePoint) const;
     static int uncheckedPreviousOffset(const Node*, int current);
     static int uncheckedPreviousOffsetForBackwardDeletion(const Node*, int current);
     static int uncheckedNextOffset(const Node*, int current);
 
@@ skipping 181 matching lines @@
 
 } // namespace WebCore
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showTree(const WebCore::Position&);
 void showTree(const WebCore::Position*);
 #endif
 
 #endif // Position_h