shill: implement Manager.GetService (error-case only)

BUG=chromium-os:20254
TEST=unittests, WiFiManager/000_SSID_Length_Limit

this gives us enough to pass the autotest for
network_WiFiManager/000_SSID_Length_Limit.

Change-Id: Ib0305e707d2203327d846be3e0b206033d6a884a
Reviewed-on: http://gerrit.chromium.org/gerrit/7567
Commit-Ready: mukesh agrawal <quiche@chromium.org>
Reviewed-by: mukesh agrawal <quiche@chromium.org>
Tested-by: mukesh agrawal <quiche@chromium.org>
diff --git a/ethernet_service.cc b/ethernet_service.cc
index 8e1cdd6..679266c 100644
--- a/ethernet_service.cc
+++ b/ethernet_service.cc
@@ -34,12 +34,9 @@
                                  EventDispatcher *dispatcher,
                                  Manager *manager,
                                  const EthernetRefPtr &device)
-    : Service(control_interface, dispatcher, manager),
-      ethernet_(device),
-      type_(flimflam::kTypeEthernet) {
+    : Service(control_interface, dispatcher, manager, flimflam::kTypeEthernet),
+      ethernet_(device) {
   set_auto_connect(true);
-
-  mutable_store()->RegisterConstString(flimflam::kTypeProperty, &type_);
 }
 
 EthernetService::~EthernetService() { }