else -> {
            if (isUpgradeRequest) {
              exchange.noRequestBody() // Failed upgrade request has no outbound data.
            }
            val responseBody = exchange.openResponseBody(response)
            response
              .newBuilder()
              .body(responseBody)
              .trailers(
                object : TrailersSource {

      trackFailure(e)
      throw e
    }
  }

  fun responseHeadersEnd(response: Response) {
    eventListener.responseHeadersEnd(call, response)
  }

  @Throws(IOException::class)
  fun openResponseBody(response: Response): ResponseBody {
    try {
      val contentType = response.header("Content-Type")
      val contentLength = codec.reportedContentLength(response)