Oilpan: Prepare moving AXObject to heap

Source/core/layout/line/AbstractInlineTextBox.h

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 54 matching lines @@
         int endIndex;
     };
 
     enum Direction {
         LeftToRight,
         RightToLeft,
         TopToBottom,
         BottomToTop
     };
 
+    ~AbstractInlineTextBox();
+
     LayoutText* layoutText() const { return m_layoutText; }
 
     PassRefPtr<AbstractInlineTextBox> nextInlineTextBox() const;
     LayoutRect bounds() const;
     unsigned len() const;
     Direction direction() const;
     void characterWidths(Vector<float>&) const;
     void wordBoundaries(Vector<WordBoundaries>&) const;
     String text() const;
     bool isFirst() const;
     bool isLast() const;
     PassRefPtr<AbstractInlineTextBox> nextOnLine() const;
     PassRefPtr<AbstractInlineTextBox> previousOnLine() const;
 
 private:
     void detach();
 
     // Weak ptrs; these are nulled when InlineTextBox::destroy() calls AbstractInlineTextBox::willDestroy.
     LayoutText* m_layoutText;
     InlineTextBox* m_inlineTextBox;
 
     typedef HashMap<InlineTextBox*, RefPtr<AbstractInlineTextBox>> InlineToAbstractInlineTextBoxHashMap;
     static InlineToAbstractInlineTextBoxHashMap* gAbstractInlineTextBoxMap;
 };
 
 } // namespace blink
 
 #endif // AbstractInlineTextBox_h