shill: Retrieve cellular signal strength in capability delegates.

Refactor only, no functional changes.

BUG=chromium-os:18735
TEST=unit tests

Change-Id: I71e5dce70fcb018a156229799a8e2e1c2bfa8e89
Reviewed-on: https://gerrit.chromium.org/gerrit/11480
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
Commit-Ready: Darin Petkov <petkov@chromium.org>
diff --git a/cellular.h b/cellular.h
index 051930c..3c0ffe8 100644
--- a/cellular.h
+++ b/cellular.h
@@ -129,6 +129,8 @@
   // unchanged otherwise.
   void Activate(const std::string &carrier, Error *error);
 
+  const CellularServiceRefPtr &service() const { return service_; }
+
   void set_modem_state(ModemState state) { modem_state_ = state; }
   ModemState modem_state() const { return modem_state_; }
 
@@ -180,6 +182,8 @@
 
   void SetGSMAccessTechnology(uint32 access_technology);
 
+  void HandleNewSignalQuality(uint32 strength);
+
   // Inherited from Device.
   virtual void Start();
   virtual void Stop();
@@ -207,8 +211,6 @@
   FRIEND_TEST(CellularTest, GetCDMAActivationStateString);
   FRIEND_TEST(CellularTest, GetCDMAActivationErrorString);
   FRIEND_TEST(CellularTest, GetCDMARegistrationState);
-  FRIEND_TEST(CellularTest, GetCDMASignalQuality);
-  FRIEND_TEST(CellularTest, GetGSMSignalQuality);
   FRIEND_TEST(CellularTest, GetModemInfo);
   FRIEND_TEST(CellularTest, GetModemStatus);
   FRIEND_TEST(CellularTest, GetStateString);
@@ -304,12 +306,6 @@
 
   void CreateService();
 
-  void GetModemSignalQuality();
-  uint32 GetCDMASignalQuality();
-  uint32 GetGSMSignalQuality();
-
-  void HandleNewSignalQuality(uint32 strength);
-
   void HandleNewCDMAActivationState(uint32 error);
 
   // Updates the GSM operator name and country based on a newly obtained network