Have EditCommand classes deal with Document references, not pointers

Source/core/editing/ApplyBlockElementCommand.h

 /*
  * Copyright (C) 2010 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 20 matching lines @@
 #ifndef ApplyBlockElementCommand_h
 #define ApplyBlockElementCommand_h
 
 #include "core/dom/QualifiedName.h"
 #include "core/editing/CompositeEditCommand.h"
 
 namespace WebCore {
 
 class ApplyBlockElementCommand : public CompositeEditCommand {
 protected:
-    ApplyBlockElementCommand(Document*, const QualifiedName& tagName, const AtomicString& inlineStyle);
-    ApplyBlockElementCommand(Document*, const QualifiedName& tagName);
+    ApplyBlockElementCommand(Document&, const QualifiedName& tagName, const AtomicString& inlineStyle);
+    ApplyBlockElementCommand(Document&, const QualifiedName& tagName);
 
     virtual void formatSelection(const VisiblePosition& startOfSelection, const VisiblePosition& endOfSelection);
     PassRefPtr<Element> createBlockElement() const;
     const QualifiedName tagName() const { return m_tagName; }
 
 private:
     virtual void doApply();
     virtual void formatRange(const Position& start, const Position& end, const Position& endOfSelection, RefPtr<Element>&) = 0;
     void rangeForParagraphSplittingTextNodesIfNeeded(const VisiblePosition&, Position&, Position&);
     VisiblePosition endOfNextParagrahSplittingTextNodesIfNeeded(VisiblePosition&, Position&, Position&);
 
     QualifiedName m_tagName;
     AtomicString m_inlineStyle;
     Position m_endOfLastParagraph;
 };
 
 }
 
 #endif