shill: vpn: Don't mark VPN services as auto-connect automatically.

BUG=chromium-os:30246
TEST=050IPSecGenesis

Change-Id: I8927e69d5cab614364f8d803a1255e458fb33015
Reviewed-on: https://gerrit.chromium.org/gerrit/21461
Tested-by: Darin Petkov <petkov@chromium.org>
Reviewed-by: mukesh agrawal <quiche@chromium.org>
Commit-Ready: Darin Petkov <petkov@chromium.org>
diff --git a/vpn_service.cc b/vpn_service.cc
index 1601ce3..a97bddf 100644
--- a/vpn_service.cc
+++ b/vpn_service.cc
@@ -113,4 +113,10 @@
   driver_->InitPropertyStore(mutable_store());
 }
 
+void VPNService::MakeFavorite() {
+  // The base MakeFavorite method also sets auto_connect_ to true
+  // which is not desirable for VPN services.
+  set_favorite(true);
+}
+
 }  // namespace shill