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

net/socket/socket_test_util.cc

Index: net/socket/socket_test_util.cc
diff --git a/net/socket/socket_test_util.cc b/net/socket/socket_test_util.cc
index f4b804bf4fb35698c65ac13ee3d4ca2c922e6133..f64b33bf2ed131076abc69a09cd67e9e9b22fa6d 100644
--- a/net/socket/socket_test_util.cc
+++ b/net/socket/socket_test_util.cc
@@ -36,6 +36,9 @@
 
 namespace net {
 
+const NetworkChangeNotifier::NetworkHandle kDefaultNetworkForTests = 1;
+const NetworkChangeNotifier::NetworkHandle kNewNetworkForTests = 2;
+
 namespace {
 
 inline char AsciifyHigh(char x) {
@@ -1245,6 +1248,7 @@ MockUDPClientSocket::MockUDPClientSocket(SocketDataProvider* data,
       read_data_(SYNCHRONOUS, ERR_UNEXPECTED),
       need_read_data_(true),
       source_port_(123),
+      network_(NetworkChangeNotifier::kInvalidNetworkHandle),
       pending_read_buf_(NULL),
       pending_read_buf_len_(0),
       net_log_(BoundNetLog::Make(net_log, NetLog::SOURCE_NONE)),
@@ -1343,16 +1347,18 @@ const BoundNetLog& MockUDPClientSocket::NetLog() const {
 
 int MockUDPClientSocket::BindToNetwork(
     NetworkChangeNotifier::NetworkHandle network) {
-  return ERR_NOT_IMPLEMENTED;
+  network_ = network;
+  return OK;
 }
 
 int MockUDPClientSocket::BindToDefaultNetwork() {
-  return ERR_NOT_IMPLEMENTED;
+  network_ = kDefaultNetworkForTests;
+  return OK;
 }
 
 NetworkChangeNotifier::NetworkHandle MockUDPClientSocket::GetBoundNetwork()
     const {
-  return NetworkChangeNotifier::kInvalidNetworkHandle;
+  return network_;
 }
 
 int MockUDPClientSocket::Connect(const IPEndPoint& address) {