code: func (c *Cluster) SendClusterEvent(event lncluster.ConfigEventType) {
  	c.mu.RLock()
  	defer c.mu.RUnlock()
  	c.configEvent <- event
  }
docs: // SendClusterEvent allows to send cluster events on the configEvent channel
  // TODO This method should not be exposed.
  // Currently it is used to notify the network controller that the keys are
  // available