[Chromecast] Add proxy server support to chromecast

chromecast/net/fake_connectivity_checker.cc

Index: chromecast/net/fake_connectivity_checker.cc
diff --git a/chromecast/net/fake_connectivity_checker.cc b/chromecast/net/fake_connectivity_checker.cc
index fc3caed6ae3e9396a796c2659150d7e84f1ec253..09eaa381d1e6a5e49cb7dc4f3eb7bd5670079e7c 100644
--- a/chromecast/net/fake_connectivity_checker.cc
+++ b/chromecast/net/fake_connectivity_checker.cc
@@ -20,6 +20,8 @@ bool FakeConnectivityChecker::Connected() const {
 void FakeConnectivityChecker::Check() {
 }
 
+void FakeConnectivityChecker::DetachFromPrefService() {}
+
 void FakeConnectivityChecker::SetConnectedForTest(bool connected) {
   if (connected_ == connected)
     return;