title: JTabbedPane - focus last focused component after tab change
body: <p>When changing tabs, JTabbedPane always focuses the first focusable Component inside the tab. 
  How can I change its behaviour so that it will either focus the last focused component or none at all? 
  Invoking requestFocus afterwards is not an option because JTabbedPane must not set the focus in the wrong field at all. </p>