Cleanup forward declared classes that are not needed.

chrome/views/dialog_delegate.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_VIEWS_DIALOG_DELEGATE_H_
 #define CHROME_VIEWS_DIALOG_DELEGATE_H_
 
 #include "chrome/views/dialog_client_view.h"
 #include "chrome/views/window_delegate.h"
 
 namespace views {
 
-class NativeButton;
 class View;
 
 ///////////////////////////////////////////////////////////////////////////////
 //
 // DialogDelegate
 //
 //  DialogDelegate is an interface implemented by objects that wish to show a
 //  dialog box Window. The window that is displayed uses this interface to
 //  determine how it should be displayed and notify the delegate object of
 //  certain events.
@@ skipping 78 matching lines @@
   // Overridden from WindowDelegate:
   virtual ClientView* CreateClientView(Window* window);
 
   // A helper for accessing the DialogClientView object contained by this
   // delegate's Window.
   DialogClientView* GetDialogClientView() const;
 };
 
 }  // namespace views
 
-#endif  // #ifndef CHROME_VIEWS_DIALOG_DELEGATE_H_
-
+#endif  // CHROME_VIEWS_DIALOG_DELEGATE_H_