Introduces ability for session to wait on a migration trigger for a new

net/quic/chromium/mock_network_change_notifier.h

Index: net/quic/chromium/mock_network_change_notifier.h
diff --git a/net/quic/chromium/mock_network_change_notifier.h b/net/quic/chromium/mock_network_change_notifier.h
index de9ef7a51db7f462a5d240edb55893b1cd6c1791..d81b4efa905bb353b9b88406bc587ae2cd05653b 100644
--- a/net/quic/chromium/mock_network_change_notifier.h
+++ b/net/quic/chromium/mock_network_change_notifier.h
@@ -39,6 +39,9 @@ class MockNetworkChangeNotifier : public NetworkChangeNotifier {
   // but does not spin the message loop to actually deliver it.
   void QueueNetworkDisconnected(NetworkChangeNotifier::NetworkHandle network);
 
+  // Delivers a CONNECTED notification to observers.
+  void NotifyNetworkConnected(NetworkChangeNotifier::NetworkHandle network);
+
  private:
   bool force_network_handles_supported_;
   NetworkChangeNotifier::NetworkList connected_networks_;