Have EditCommand classes deal with Document references, not pointers

Source/core/editing/BreakBlockquoteCommand.h

Index: Source/core/editing/BreakBlockquoteCommand.h
diff --git a/Source/core/editing/BreakBlockquoteCommand.h b/Source/core/editing/BreakBlockquoteCommand.h
index 31941d3acbe082d95c6d00ac4f79fc9b84bd9d65..359777c82656cb3f03e3dec86d63d4a60d746463 100644
--- a/Source/core/editing/BreakBlockquoteCommand.h
+++ b/Source/core/editing/BreakBlockquoteCommand.h
@@ -32,13 +32,13 @@ namespace WebCore {
 
 class BreakBlockquoteCommand : public CompositeEditCommand {
 public:
-    static PassRefPtr<BreakBlockquoteCommand> create(Document* document)
+    static PassRefPtr<BreakBlockquoteCommand> create(Document& document)
     {
         return adoptRef(new BreakBlockquoteCommand(document));
     }
 
 private:
-    explicit BreakBlockquoteCommand(Document*);
+    explicit BreakBlockquoteCommand(Document&);
     virtual void doApply();
 };