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

net/quic/quic_chromium_client_session.h

Index: net/quic/quic_chromium_client_session.h
diff --git a/net/quic/quic_chromium_client_session.h b/net/quic/quic_chromium_client_session.h
index feb071042f26df69280ab0b8371ef09a502be281..6767afd630d22580d97ab368591252c5541d3a37 100644
--- a/net/quic/quic_chromium_client_session.h
+++ b/net/quic/quic_chromium_client_session.h
@@ -177,7 +177,7 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
   // Resumes a crypto handshake with the server after a timeout.
   int ResumeCryptoConnect(const CompletionCallback& callback);
 
-  // Causes the QuicConnectionHelper to start reading from the socket
+  // Causes the QuicConnectionHelper to start reading from all sockets
   // and passing the data along to the QuicConnection.
   void StartReading();
 
@@ -210,6 +210,13 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
 
   QuicDisabledReason disabled_reason() const { return disabled_reason_; }
 
+  // Call to add a new socket to the session. Takes ownership of |socket|.
+  void AddSocket(scoped_ptr<DatagramClientSocket> socket);

[Ryan Hamilton, 2015/09/08 04:09:38]

Do we ever remove sockets? How shall we handle read/write errors?

[Jana, 2015/11/17 01:50:08]

We don't remove sockets at this point. This is why there's a max number of
sockets that we create. Since there's only one Writer at the moment, that error
processing shouldn't change. We maintain multiple readers however, and we need
to catch read errors. I'll do some work on figuring out how to catch
OnReadError.

+
+  // Call to add a new PacketReader to the session. Returns true if reader was
+  // successfully added to the session. Takes ownership of |reader|.
+  bool AddPacketReader(QuicPacketReader* reader);

[Ryan Hamilton, 2015/09/08 04:09:37]

Should this be a scoped_ptr?

[Jana, 2015/11/17 01:50:08]

Done.

+

[Ryan Hamilton, 2015/09/08 04:09:38]

It's a bit odd that we need a socket, reader and writer but only need to pass in
a reader and a socket. This is probably out of scope for this CL...

[Jana, 2015/11/17 01:50:08]

Fixed in the new version, PTAL.

  protected:
   // QuicSession methods:
   QuicDataStream* CreateIncomingDynamicStream(QuicStreamId id) override;
@@ -259,7 +266,7 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
   bool require_confirmation_;
   scoped_ptr<QuicCryptoClientStream> crypto_stream_;
   QuicStreamFactory* stream_factory_;
-  scoped_ptr<DatagramClientSocket> socket_;
+  std::vector<scoped_ptr<DatagramClientSocket>> sockets_;
   TransportSecurityState* transport_security_state_;
   scoped_ptr<QuicServerInfo> server_info_;
   scoped_ptr<CertVerifyResult> cert_verify_result_;
@@ -270,7 +277,7 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
   size_t num_total_streams_;
   base::TaskRunner* task_runner_;
   BoundNetLog net_log_;
-  QuicPacketReader packet_reader_;
+  std::vector<scoped_ptr<QuicPacketReader>> packet_readers_;
   base::TimeTicks dns_resolution_end_time_;
   base::TimeTicks handshake_start_;  // Time the handshake was started.
   scoped_ptr<QuicConnectionLogger> logger_;