Early connection migration in QUIC.

net/http/http_network_session.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.
 
 #ifndef NET_HTTP_HTTP_NETWORK_SESSION_H_
 #define NET_HTTP_HTTP_NETWORK_SESSION_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 168 matching lines @@
     // Set of QUIC tags to send in the handshake's connection options.
     QuicTagVector quic_connection_options;
     // If true, all QUIC sessions are closed when any local IP address changes.
     bool quic_close_sessions_on_ip_change;
     // Specifes QUIC idle connection state lifetime.
     int quic_idle_connection_timeout_seconds;
     // If true, disable preconnections if QUIC can do 0RTT.
     bool quic_disable_preconnect_if_0rtt;
     // List of hosts for which QUIC is explicitly whitelisted.
     std::unordered_set<std::string> quic_host_whitelist;
-    // If true, active QUIC sessions may be migrated onto new IPs when network
-    // changes.
+    // If true, active QUIC sessions may be migrated onto a new network when
+    // the platform indicates that the default network is changing.
     bool quic_migrate_sessions_on_network_change;
+    // If true, active QUIC sessions experiencing poor connectivity may be
+    // migrated onto a new network.
+    bool quic_migrate_sessions_early;
     ProxyDelegate* proxy_delegate;
     // Enable support for Token Binding.
     bool enable_token_binding;
   };
 
   enum SocketPoolType {
     NORMAL_SOCKET_POOL,
     WEBSOCKET_SOCKET_POOL,
     NUM_SOCKET_POOL_TYPES
   };
@@ skipping 101 matching lines @@
 
   NextProtoVector next_protos_;
   bool enabled_protocols_[NUM_VALID_ALTERNATE_PROTOCOLS];
 
   Params params_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_NETWORK_SESSION_H_