shill: Get and update the GSM signal strength on registration state transition.

BUG=chromium-os:19777
TEST=unit tests, tested on device

Change-Id: I2fa1292f5c3413a685ba87bc827aa34943109b37
Reviewed-on: http://gerrit.chromium.org/gerrit/6845
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
diff --git a/mock_modem_gsm_network_proxy.h b/mock_modem_gsm_network_proxy.h
index ebf6bd6..bec2180 100644
--- a/mock_modem_gsm_network_proxy.h
+++ b/mock_modem_gsm_network_proxy.h
@@ -17,8 +17,9 @@
   MockModemGSMNetworkProxy();
   virtual ~MockModemGSMNetworkProxy();
 
-  MOCK_METHOD1(Register, void(const std::string &network_id));
   MOCK_METHOD0(GetRegistrationInfo, RegistrationInfo());
+  MOCK_METHOD0(GetSignalQuality, uint32());
+  MOCK_METHOD1(Register, void(const std::string &network_id));
   MOCK_METHOD0(AccessTechnology, uint32());
 
  private: