Add a dedicated error code for TLS 1.3 interference.

net/log/net_log_event_type_list.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // NOTE: No header guards are used, since this file is intended to be expanded
 // directly into net_log.h. DO NOT include this file anywhere else.
 
 // In the event of a failure, a many end events will have a |net_error|
 // parameter with the integer error code associated with the failure.  Most
 // of these parameters are not individually documented.
@@ skipping 545 matching lines @@
 
 // An SSL connection needs to be retried with more cipher suites because the
 // server may require a deprecated cipher suite. The following parameters are
 // attached to the event:
 //   {
 //     "host_and_port": <String encoding the host and port>,
 //     "net_error": <Net integer error code>,
 //   }
 EVENT_TYPE(SSL_CIPHER_FALLBACK)
 
+// An SSL connection needs to be retried with a lower protocol version to detect
+// if the error was due to a middlebox interfering with the protocol version we
+// offered.
+// The following parameters are attached to the event:
+//   {
+//     "net_error": <Net integer error code which triggered the probe>,
+//   }
+EVENT_TYPE(SSL_VERSION_INTERFERENCE_PROBE)
+
 // We found that our prediction of the server's certificates was correct and
 // we merged the verification with the SSLHostInfo. (Note: now obsolete.)
 EVENT_TYPE(SSL_VERIFICATION_MERGED)
 
 // An SSL error occurred while calling an NSS function not directly related to
 // one of the above activities.  Can also be used when more information than
 // is provided by just an error code is needed:
 //   {
 //     "function": <Name of the NSS function, as a string>,
 //     "param": <Most relevant parameter, if any>,
@@ skipping 2596 matching lines @@
 // quality of the network has changed.
 // parameters:
 //  {
 //    "http_rtt": <Current estimate of the HTTP RTT>,
 //    "transport_rtt": <Current estimate of the transport RTT>,
 //    "downstream_throughput": <Current estimate of the downstream throughput>,
 //    "effective_connection_type": <Current estimate of the effective connection
 //                                  type>,
 //  }
 EVENT_TYPE(NETWORK_QUALITY_CHANGED)