code: func (c *ServiceWorker) DispatchSyncEvent(origin string, registrationId string, tag string, lastChance bool) (*gcdmessage.ChromeResponse, error) {
  	var v ServiceWorkerDispatchSyncEventParams
  	v.Origin = origin
  	v.RegistrationId = registrationId
  	v.Tag = tag
  	v.LastChance = lastChance
  	return c.DispatchSyncEventWithParams(&v)
  }
docs: // DispatchSyncEvent -
  // origin -
  // registrationId -
  // tag -
  // lastChance -