code: private void clearDrag() {
  
          if (m_listItemWidget != null) {
              Iterator<Widget> buttonIterator = m_listItemWidget.getButtonPanel().iterator();
              while (buttonIterator.hasNext()) {
                  Widget button = buttonIterator.next();
                  button.getElement().getStyle().clearVisibility();
              }
          }
          if (m_helper != null) {
              m_helper.removeFromParent();
              m_helper = null;
          }
          if (m_provisionalParent != null) {
              m_provisionalParent.removeFromParent();
              m_provisionalParent = null;
          }
          setVisible(true);
  
      }
docs: Called when a drag operation for this widget is stopped.<p>