@Test
 public void test_canRemoveFormItemClickHandlerWithHandlerRegistration() {
   final FormItemClickHandler handler = mock(FormItemClickHandler.class);
   final HandlerRegistration registration = formItemIcon.addFormItemClickHandler(handler);
   registration.removeHandler();
   assertFalse(formItemIcon.getFormItemClickHandlers().contains(handler));
 }
 @Test
 public void test_canAddFormItemIconClickHandler() {
   final FormItemClickHandler handler = mock(FormItemClickHandler.class);
   formItemIcon.addFormItemClickHandler(handler);
   assertTrue(formItemIcon.getFormItemClickHandlers().contains(handler));
 }