*/
  internal fun sendDegradedPingLater() {
    this.withLock {
      if (degradedPongsReceived < degradedPingsSent) return // Already awaiting a degraded pong.
      degradedPingsSent++
      degradedPongDeadlineNs = System.nanoTime() + DEGRADED_PONG_TIMEOUT_NS
    }
    writerQueue.execute("$connectionName ping") {
      writePing(false, DEGRADED_PING, 0)
    }
  }

  class Builder(

    peer.sendFrame().ping(true, Http2Connection.AWAIT_PING, 5)
    peer.play()

    // Play it back.
    val connection = connect(peer)
    val pingAtNanos = System.nanoTime()
    connection.writePingAndAwaitPong()
    val elapsedNanos = System.nanoTime() - pingAtNanos
    assertThat(elapsedNanos).isGreaterThan(0L)
    assertThat(elapsedNanos).isLessThan(TimeUnit.SECONDS.toNanos(1))