// larger struct and have the Mutex and Cond's memory in the same
// allocation.
func (cw *http2closeWaiter) Init() {
	*cw = make(chan struct{})
}

// Close marks the closeWaiter as closed and unblocks any waiters.
func (cw http2closeWaiter) Close() {
	close(cw)
}

// Wait waits for the closeWaiter to become closed.
func (cw http2closeWaiter) Wait() {
	<-cw
}