code: public void displayFeedback (String bundle, String message)
      {
          displaySystem(bundle, message, SystemMessage.FEEDBACK, PLACE_CHAT_TYPE);
      }
docs: Display a system FEEDBACK message as if it had come from the server. The localtype of the
  message will be PLACE_CHAT_TYPE.
  
  Feedback messages are sent in direct response to a user action, usually to indicate success
  or failure of the user's action.