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

net/udp/udp_client_socket.cc

Index: net/udp/udp_client_socket.cc
diff --git a/net/udp/udp_client_socket.cc b/net/udp/udp_client_socket.cc
index ca1f9e2439dd68c9f623a8b416dc5c9ae2372873..4d5fecd9676b1c9b7463c92d132062a5af757c45 100644
--- a/net/udp/udp_client_socket.cc
+++ b/net/udp/udp_client_socket.cc
@@ -24,6 +24,12 @@ int UDPClientSocket::BindToNetwork(
   return socket_.BindToNetwork(network);
 }
 
+int UDPClientSocket::BindToDefaultNetwork() {
+  NetworkChangeNotifier::NetworkHandle network =
+      NetworkChangeNotifier::GetDefaultNetwork();
+  return BindToNetwork(network);

[Ryan Hamilton, 2015/11/18 22:23:36]

I'm not sure there is much benefit to this method since it seems to be
equivalent to:

socket->BindToNetwork(NetworkChangeNotifier::GetDefaultNetwork());

I think it would be cleaner to just use the method. It also means that in
QuicStreamFactory instead of passing in kInvalid and then checking to see if
network = kInvalue and then possibly calling this method, you could just pass
NetworkChangeNotifier::GetDefaultNetwork() into the Create socket method.

[pauljensen, 2015/11/19 15:25:43]

Jana's implementation and Ryan's suggestion both suffer from a race between
getting the default and binding to it, and the default changing.  This was the
point of my
https://codereview.chromium.org/1416213003/diff/1/net/udp/udp_client_socket.c...

[Jana, 2015/11/21 02:21:22]

What Paul said. Paul CL will be submitted before mine, so I will use whatever
that CL has.

+}
+
 int UDPClientSocket::Connect(const IPEndPoint& address) {
   int rv = socket_.Open(address.GetFamily());
   if (rv != OK)