Make stylesheet owner node a reference instead of pointer.

third_party/WebKit/Source/core/dom/StyleElement.h

 /*
  * Copyright (C) 2006, 2007 Rob Buis
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 34 matching lines @@
 
     virtual const AtomicString& type() const = 0;
     virtual const AtomicString& media() const = 0;
 
     CSSStyleSheet* sheet() const { return m_sheet.get(); }
 
     bool isLoading() const;
     bool sheetLoaded(Document&);
     void startLoadingDynamicSheet(Document&);
 
-    void insertedInto(Element*, ContainerNode* insertionPoint);
-    void removedFrom(Element*, ContainerNode* insertionPoint);
-    ProcessingResult processStyleSheet(Document&, Element*);
-    ProcessingResult childrenChanged(Element*);
-    ProcessingResult finishParsingChildren(Element*);
+    void insertedInto(const Element&, ContainerNode* insertionPoint);
+    void removedFrom(Element&, ContainerNode* insertionPoint);
+    ProcessingResult processStyleSheet(Document&, Element&);
+    ProcessingResult childrenChanged(Element&);
+    ProcessingResult finishParsingChildren(Element&);
 
     Member<CSSStyleSheet> m_sheet;
 
 private:
-    ProcessingResult createSheet(Element*, const String& text = String());
-    ProcessingResult process(Element*);
-    void clearSheet(Element* ownerElement = 0);
+    ProcessingResult createSheet(Element&, const String& text = String());
+    ProcessingResult process(Element&);
+    void clearSheet(Element& ownerElement);
 
     bool m_createdByParser : 1;
     bool m_loading : 1;
     bool m_registeredAsCandidate : 1;
     TextPosition m_startPosition;
     StyleEngineContext m_styleEngineContext;
 };
 
 } // namespace blink
 
 #endif