Have StyleElement API take Document as a reference

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 24 matching lines @@
     StyleElement(Document*, bool createdByParser);
     virtual ~StyleElement();
 
 protected:
     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*);
+    bool sheetLoaded(Document&);
+    void startLoadingDynamicSheet(Document&);
 
-    void processStyleSheet(Document*, Element*);
-    void removedFromDocument(Document*, Element*, ContainerNode* scopingNode = 0);
-    void clearDocumentData(Document*, Element*);
+    void processStyleSheet(Document&, Element*);
+    void removedFromDocument(Document&, Element*, ContainerNode* scopingNode = 0);
+    void clearDocumentData(Document&, Element*);
     void childrenChanged(Element*);
     void finishParsingChildren(Element*);
 
     RefPtr<CSSStyleSheet> m_sheet;
 
 private:
     void createSheet(Element*, const String& text = String());
     void process(Element*);
     void clearSheet();
 
     bool m_createdByParser;
     bool m_loading;
     TextPosition m_startPosition;
 };
 
 }
 
 #endif