code: public static ThemeController get() {
  		if (ThemeController.instance == null) {
  			ThemeController.instance = GWT.create(ThemeController.class);
  		}
  		return ThemeController.instance;
  	}
docs: Gets the singleton.
  <p>
  The singleton is instantiated with GWT.create(ThemeController.class), so you can customize your
  implementation in your module .gwt.xml
  </p>
  
  @return the theme controller