*  New: `OkHttpClient.x509TrustManager` accessor.
 *  New: Permit [new WebSocket response codes][iana_websocket]: 1012 (Service Restart), 1013 (Try
    Again Later), and 1014 (invalid response from the upstream).
 *  New: Build with Kotlin 1.3.41, BouncyCastle 1.62, and Conscrypt 2.2.1.
 *  Fix: Recover gracefully when a coalesced connection immediately goes unhealthy.

  private var nextQueueName = 10000
  private var coordinatorWaiting = false
  private var coordinatorWakeUpAt = 0L

  /**
   * When we need a new thread to run tasks, we call [Backend.execute]. A few microseconds later we
   * expect a newly-started thread to call [Runnable.run]. We shouldn't request new threads until
   * the already-requested ones are in service, otherwise we might create more threads than we need.
   *

   * }
   * ```
   *
   * RFC 5280, section 4.1.2.5:
   *
   * > CAs conforming to this profile MUST always encode certificate validity dates through the year
   * > 2049 as UTCTime; certificate validity dates in 2050 or later MUST be encoded as
   * > GeneralizedTime.
   */
  internal val time: DerAdapter<Long> =
    object : DerAdapter<Long> {
      override fun matches(header: DerHeader): Boolean {

        requireMultiplexed = planToReplace != null && planToReplace.isReady,
      ) ?: return null

    // If we coalesced our connection, remember the replaced connection's route. That way if the
    // coalesced connection later fails we don't waste a valid route.
    if (planToReplace != null) {
      nextRouteToTry = planToReplace.route
      planToReplace.closeQuietly()
    }

    connectionUser.connectionAcquired(result)

 *  Fix: Don't drop uncaught exceptions thrown in async calls.
 *  Fix: Throw an exception eagerly when a request body is not legal. Previously
    we ignored the problem at request-building time, only to crash later with a
    `NullPointerException`.
 *  Fix: Include a backwards-compatible `OkHttp-Response-Source` header with
    `OkUrlFactory `responses.
 *  Fix: Don't include a default User-Agent header in requests made with the Call

      request.header("If-Modified-Since") != null || request.header("If-None-Match") != null
  }

  companion object {
    /** Returns true if [response] can be stored to later serve another request. */
    fun isCacheable(
      response: Response,
      request: Request,
    ): Boolean {
      // Always go to network for uncacheable response codes (RFC 7231 section 6.1), This

      }

      return 0L // run again immediately to create more connections if needed
    } catch (e: IOException) {
      // No need to log, user.connectFailed() will already have been called. Just try again later.
      return state.policy.backoffDelayMillis.jitterBy(state.policy.backoffJitterMillis) * 1_000_000
    }
  }

  private fun Long.jitterBy(amount: Int): Long {