@Override
 protected void installListeners() {
   super.installListeners();
   scrollbar.addMouseMotionListener(this);
   scrollbar.addMouseListener(this);
   myErrorStripeButton.addMouseMotionListener(this);
   myErrorStripeButton.addMouseListener(this);
 }
    public void setPopupHandler(final PopupHandler handler) {
      if (myHandler != null) {
        scrollbar.removeMouseListener(myHandler);
        myErrorStripeButton.removeMouseListener(myHandler);
      }

      myHandler = handler;
      scrollbar.addMouseListener(handler);
      myErrorStripeButton.addMouseListener(myHandler);
    }