Oilpan: Validate pointers stored in Member

Source/core/editing/iterators/TextIterator.h

 /*
  * Copyright (C) 2004, 2006, 2009 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 146 matching lines @@
     RawPtrWillBeMember<Node> m_pastEndNode;
 
     // Used when there is still some pending text from the current node; when these
     // are false and 0, we go back to normal iterating.
     bool m_needsAnotherNewline;
     InlineTextBox* m_textBox;
     // Used when iteration over :first-letter text to save pointer to
     // remaining text box.
     InlineTextBox* m_remainingTextBox;
     // Used to point to LayoutText object for :first-letter.
-    RawPtrWillBeMember<LayoutText> m_firstLetterText;
+    LayoutText* m_firstLetterText;
 
     // Used to do the whitespace collapsing logic.
     RawPtrWillBeMember<Text> m_lastTextNode;
     bool m_lastTextNodeEndedWithCollapsedSpace;
 
     // Used when text boxes are out of order (Hebrew/Arabic w/ embeded LTR text)
     Vector<InlineTextBox*> m_sortedTextBoxes;
     size_t m_sortedTextBoxesPosition;
 
     const TextIteratorBehaviorFlags m_behavior;
 
     // Used when deciding text fragment created by :first-letter should be looked into.
     bool m_handledFirstLetter;
     // Used when stopsOnFormControls() is true to determine if the iterator should keep advancing.
     bool m_shouldStop;
 
     // Contains state of emitted text.
     TextIteratorTextState m_textState;
 };
 
 extern template class CORE_EXTERN_TEMPLATE_EXPORT TextIteratorAlgorithm<EditingStrategy>;
 extern template class CORE_EXTERN_TEMPLATE_EXPORT TextIteratorAlgorithm<EditingInComposedTreeStrategy>;
 
 using TextIterator = TextIteratorAlgorithm<EditingStrategy>;
 using TextIteratorInComposedTree = TextIteratorAlgorithm<EditingInComposedTreeStrategy>;
 
 } // namespace blink
 
 #endif // TextIterator_h