Migrates QUIC sessions to a new network when old network is (about to be) disconnected.

chrome/browser/io_thread.cc

 // 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.
 
 #include "chrome/browser/io_thread.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/base64.h"
@@ skipping 1162 matching lines @@
       &params->quic_supported_versions);
   params->quic_connection_options = globals.quic_connection_options;
   globals.quic_close_sessions_on_ip_change.CopyToIfSet(
       &params->quic_close_sessions_on_ip_change);
   globals.quic_idle_connection_timeout_seconds.CopyToIfSet(
       &params->quic_idle_connection_timeout_seconds);
   globals.quic_disable_preconnect_if_0rtt.CopyToIfSet(
       &params->quic_disable_preconnect_if_0rtt);
   if (!globals.quic_host_whitelist.empty())
     params->quic_host_whitelist = globals.quic_host_whitelist;
-
+  globals.quic_migrate_sessions_on_network_change.CopyToIfSet(
+      &params->quic_migrate_sessions_on_network_change);
   globals.origin_to_force_quic_on.CopyToIfSet(
       &params->origin_to_force_quic_on);
   params->enable_user_alternate_protocol_ports =
       globals.enable_user_alternate_protocol_ports;
 }
 
 base::TimeTicks IOThread::creation_time() const {
   return creation_time_;
 }
 
@@ skipping 120 matching lines @@
     int idle_connection_timeout_seconds = GetQuicIdleConnectionTimeoutSeconds(
         quic_trial_params);
     if (idle_connection_timeout_seconds != 0) {
       globals->quic_idle_connection_timeout_seconds.set(
           idle_connection_timeout_seconds);
     }
     globals->quic_disable_preconnect_if_0rtt.set(
         ShouldQuicDisablePreConnectIfZeroRtt(quic_trial_params));
     globals->quic_host_whitelist =
         GetQuicHostWhitelist(command_line, quic_trial_params);
+    globals->quic_migrate_sessions_on_network_change.set(
+        ShouldQuicMigrateSessionsOnNetworkChange(quic_trial_params));
   }
 
   size_t max_packet_length = GetQuicMaxPacketLength(command_line,
                                                     quic_trial_params);
   if (max_packet_length != 0) {
     globals->quic_max_packet_length.set(max_packet_length);
   }
 
   std::string quic_user_agent_id = chrome::GetChannelString();
   if (!quic_user_agent_id.empty())
@@ skipping 257 matching lines @@
   }
   std::unordered_set<std::string> hosts;
   for (const std::string& host :base::SplitString(whitelist, ",",
                                                   base::TRIM_WHITESPACE,
                                                   base::SPLIT_WANT_ALL)) {
     hosts.insert(host);
   }
   return hosts;
 }
 
+bool IOThread::ShouldQuicMigrateSessionsOnNetworkChange(
+    const VariationParameters& quic_trial_params) {
+  return base::LowerCaseEqualsASCII(
+      GetVariationParam(quic_trial_params,
+                        "migrate_sessions_on_network_change"),
+      "true");
+}
+
 size_t IOThread::GetQuicMaxPacketLength(
     const base::CommandLine& command_line,
     const VariationParameters& quic_trial_params) {
   if (command_line.HasSwitch(switches::kQuicMaxPacketLength)) {
     unsigned value;
     if (!base::StringToUint(
             command_line.GetSwitchValueASCII(switches::kQuicMaxPacketLength),
             &value)) {
       return 0;
     }
@@ skipping 159 matching lines @@
       std::move(job_factory);
 
   context->set_job_factory(
       globals->proxy_script_fetcher_url_request_job_factory.get());
 
   // TODO(rtenneti): We should probably use HttpServerPropertiesManager for the
   // system URLRequestContext too. There's no reason this should be tied to a
   // profile.
   return context;
 }