* CONNECT tunnels. Note that CONNECT tunnels are significantly less capable than connections.
   */
  interface Carrier {
    val route: Route

    fun trackFailure(
      call: RealCall,
      e: IOException?,
    )

    fun noNewExchanges()

    fun cancel()
  }

  companion object {
    /**

    }

    call.eventListener.connectionAcquired(call, connection)
    connection.connectionListener.connectionAcquired(connection, call)
    return connection
  }

  override fun trackFailure(
    call: RealCall,
    e: IOException?,
  ) {
    // Do nothing.
  }

  override fun noNewExchanges() {
    // Do nothing.
  }

  override fun cancel() {
    canceled = true