code: function executeDispatch(event, simulated, listener, inst) {
    var type = event.type || 'unknown-event';
    event.currentTarget = EventPluginUtils.getNodeFromInstance(inst);
    if (simulated) {
      ReactErrorUtils.invokeGuardedCallbackWithCatch(type, listener, event);
    } else {
      ReactErrorUtils.invokeGuardedCallback(type, listener, event);
    }
    event.currentTarget = null;
  }
docs: Dispatch the event to the listener.
  @param {SyntheticEvent} event SyntheticEvent to handle
  @param {boolean} simulated If the event is simulated (changes exn behavior)
  @param {function} listener Application-level callback
  @param {*} inst Internal component instance