@Override
  public void setDropPossible(@NlsContexts.PopupContent String aExpectedResult, DropActionHandler aHandler) {
    myDropPossible = true;
    myExpectedDropResult = aExpectedResult;
    myDropHandler = aHandler;
  }
@Override
  public void setDropPossible(@NlsContexts.PopupContent String aExpectedResult, DropActionHandler aHandler)