could use new flow control capacity before acknowledging it, causing strict HTTP/2 servers to
    fail the call.


## Version 4.1.1

_2019-09-05_

 *  Fix: Don't drop repeated headers when validating cached responses. In our Kotlin upgrade we
    introduced a regression where we iterated the number of unique header names rather than then

     *
     * ## Upstream
     *
     * In this case the current thread is assigned as the upstream reader. We read bytes from
     * upstream and copy them to both the file and to the buffer. Finally we release the upstream
     * reader lock and return the new bytes.
     *
     * ## The file
     *
     * In this case we copy bytes from the file to the [sink].
     *
     * ## The buffer
     *

    lock.assertHeld()

    // If this connection is not accepting new exchanges, we're done.
    if (calls.size >= allocationLimit || noNewExchanges) return false

    // If the non-host fields of the address don't overlap, we're done.
    if (!this.route.address.equalsNonHost(address)) return false

    // If the host exactly matches, we're done: this connection can carry the address.

          if (rule.startsWith(EXCEPTION_RULE_MARKER)) {
            rule = rule.substring(1)
            // We use '\n' for end of value.
            totalExceptionRuleBytes += rule.size + 1
            sortedExceptionRules.add(rule)
          } else {
            totalRuleBytes += rule.size + 1 // We use '\n' for end of value.
            sortedRules.add(rule)
          }
        }
      }

      if (input.startsWith(":", startIndex = i)) {
        i++
      } else if (input.startsWith(".", startIndex = i)) {
        // If we see a '.', rewind to the beginning of the previous group and parse as IPv4.
        if (!decodeIpv4Suffix(input, groupOffset, limit, address, b - 2)) return null
        b += 2 // We rewound two bytes and then added four.
        break
      } else {
        return null // Wrong delimiter.
      }
    }

    }
  }

  override fun loadForRequest(url: HttpUrl): List<Cookie> {
    val cookieHeaders =
      try {
        // The RI passes all headers. We don't have 'em, so we don't pass 'em!
        cookieHandler.get(url.toUri(), emptyMap<String, List<String>>())
      } catch (e: IOException) {
        Platform.get().log("Loading cookies failed for " + url.resolve("/...")!!, WARN, e)

    printEvent("dnsStart");
  }

  @Override public void dnsEnd(Call call, String domainName, List<InetAddress> inetAddressList) {
    printEvent("dnsEnd");
  }

  ...
}
```

We make a couple calls:

```java
Request request = new Request.Builder()
    .url("https://publicobject.com/helloworld.txt")
    .build();

System.out.println("REQUEST 1 (new connection)");

 * and the implementation should respond with a new request that sets the "Authorization" header.
 *
 * ```java
 * if (response.request().header("Authorization") != null) {
 *   return null; // Give up, we've already failed to authenticate.
 * }
 *
 * String credential = Credentials.basic(...)
 * return response.request().newBuilder()
 *     .header("Authorization", credential)
 *     .build();
 * ```
 *

      "FGHIJKLMNOPQRSTUVWXYZ",
    )
    inputStream.close()
    assertContent("ABCDEFGHIJKLMNOPQRSTUVWXYZ", getResponse(newRequest("/")))
  }

  /**
   * We've had a bug where we forget the HTTP response when we see response code 401. This causes a
   * new HTTP request to be issued for every call into the URLConnection.
   */
  @Test
  fun unauthorizedResponseHandling() {
    val mockResponse =

        if (toClose != null) {
          connection.connectionListener.connectionClosed(connection)
        }
      } else {
        check(toClose == null) // If we still have a connection we shouldn't be closing any sockets.
      }
    }

    val result = timeoutExit(e)
    if (e != null) {
      eventListener.callFailed(this, result!!)
    } else {