for {
		w := q.peekFront()
		if w == nil || w.waiting() {
			return cleaned
		}
		q.popFront()
		cleaned = true
	}
}

// cleanFrontCanceled pops any wantConns with canceled dials from the head of the queue.
func (q *wantConnQueue) cleanFrontCanceled() {
	for {
		w := q.peekFront()
		if w == nil || w.cancelCtx != nil {
			return
		}
		q.popFront()
	}
}