}
      throw IllegalStateException("too early; can't read the trailers yet")
    }
  }

  /**
   * Sends a reply to an incoming stream.
   *
   * @param outFinished true to eagerly finish the output stream to send data to the remote peer.
   *     Corresponds to `FLAG_FIN`.
   * @param flushHeaders true to force flush the response headers. This should be true unless the