title: GWT: Disable dragging in DialogBox
body: <p>Is it possible to disable dragging in a <code>com.google.gwt.user.client.ui.DialogBox</code> instance?  I like my container to have a title bar but it should be in a fixed position and the user shouldn't be capable of moving it.</p>
  
  <p>If it is not possible, what's the GWT widget that fits for the job?</p>