// The purpose of this terrible hack is so that watchers added after an event
// won't ever see that event, and will always see any event after they are
// added.
func (m *Broadcaster) blockQueue(f func()) {
	m.incomingBlock.Lock()
	defer m.incomingBlock.Unlock()
	select {
	case <-m.stopped:
		return
	default:
	}
	var wg sync.WaitGroup
	wg.Add(1)
	m.incoming <- Event{

	// 1. Close watcher stopchannel, so watchers are closed independently of the
	// eventBroadcaster
	// 2. Shutdown the m.incoming slightly Before m.stopped so that the watcher's
	// call of Blockqueue can pass the m.stopped check.
	m.blockQueue(func() {
		close(stopCh)
		close(m.incoming)
		time.Sleep(1 * time.Millisecond)
		close(m.stopped)
	})
	m.distributing.Wait()