internal fun removeStream(streamId: Int): Http2Stream? {
    this.withLock {
      val stream = streams.remove(streamId)

      // The removed stream may be blocked on a connection-wide window update.
      condition.signalAll()

      return stream
    }
  }

  internal fun updateConnectionFlowControl(read: Long) {
    this.withLock {
      readBytes.update(total = read)