// Play it back.
    val connection = connect(peer)
    connection.newStream(headerEntries("b", "banana"), false)
    assertThat(connection.openStreamCount()).isEqualTo(1)
    connection.writePingAndAwaitPong() // Ensure that the SYN_REPLY has been received.
    assertThat(connection.openStreamCount()).isEqualTo(0)

    // Verify the peer received what was expected.
    val synStream = peer.takeFrame()

          return@schedule pingIntervalNanos
        }
      }
    }
  }

  /**
   * Returns the number of [open streams][Http2Stream.isOpen] on this connection.
   */
  fun openStreamCount(): Int = withLock { streams.size }

  fun getStream(id: Int): Http2Stream? = withLock { streams[id] }

  internal fun removeStream(streamId: Int): Http2Stream? {
    withLock {