code: public void updateTabTitle (Tab tab) {
  		TabButtonTable table = tabsButtonMap.get(tab);
  		if (table == null) {
  			throwNotBelongingTabException(tab);
  		}
  		table.button.setText(getTabTitle(tab));
  	}
docs: Must be called when you want to update tab title. If tab is dirty an '*' is added before title. This is called automatically
  if using {@link Tab#setDirty(boolean)}
  @param tab that title will be updated