Have EditCommand classes deal with Document references, not pointers

Source/core/editing/ReplaceSelectionCommand.h

Index: Source/core/editing/ReplaceSelectionCommand.h
diff --git a/Source/core/editing/ReplaceSelectionCommand.h b/Source/core/editing/ReplaceSelectionCommand.h
index fce407d6057bb9b73bc0aef896d06f594501aca1..b6eacc700190dd8efbd28142312af49c2133e8c8 100644
--- a/Source/core/editing/ReplaceSelectionCommand.h
+++ b/Source/core/editing/ReplaceSelectionCommand.h
@@ -47,13 +47,13 @@ public:
 
     typedef unsigned CommandOptions;
 
-    static PassRefPtr<ReplaceSelectionCommand> create(Document* document, PassRefPtr<DocumentFragment> fragment, CommandOptions options, EditAction action = EditActionPaste)
+    static PassRefPtr<ReplaceSelectionCommand> create(Document& document, PassRefPtr<DocumentFragment> fragment, CommandOptions options, EditAction action = EditActionPaste)
     {
         return adoptRef(new ReplaceSelectionCommand(document, fragment, options, action));
     }
 
 private:
-    ReplaceSelectionCommand(Document*, PassRefPtr<DocumentFragment>, CommandOptions, EditAction);
+    ReplaceSelectionCommand(Document&, PassRefPtr<DocumentFragment>, CommandOptions, EditAction);
 
     virtual void doApply();
     virtual EditAction editingAction() const;