shill: cellular: Reorganize default implementations in capability code.

This CL cleans up the cellular capability code as follows:
- Reorganizes the default implementations of method in the cellular
  capability classes
- Removes duplicated override methods
- Reorders method declarations in header files to group related methods
  together
- Adds the override keyword to override methods and fixes mismatched
  method signatures

BUG=None
TEST=Build and run unit tests.

Change-Id: If4adcd5852fc56cd472620385fdd0c5b358d0b11
Reviewed-on: https://chromium-review.googlesource.com/185048
Reviewed-by: Prathmesh Prabhu <pprabhu@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
diff --git a/cellular_capability_universal_cdma.cc b/cellular_capability_universal_cdma.cc
index df1e589..7b36dc6 100644
--- a/cellular_capability_universal_cdma.cc
+++ b/cellular_capability_universal_cdma.cc
@@ -47,9 +47,7 @@
     Cellular *cellular,
     ProxyFactory *proxy_factory,
     ModemInfo *modem_info)
-    : CellularCapabilityUniversal(cellular,
-                                  proxy_factory,
-                                  modem_info),
+    : CellularCapabilityUniversal(cellular, proxy_factory, modem_info),
       weak_cdma_ptr_factory_(this),
       activation_state_(MM_MODEM_CDMA_ACTIVATION_STATE_NOT_ACTIVATED),
       cdma_1x_registration_state_(MM_MODEM_CDMA_REGISTRATION_STATE_UNKNOWN),
@@ -61,6 +59,8 @@
   // See crbug.com/197330.
 }
 
+CellularCapabilityUniversalCDMA::~CellularCapabilityUniversalCDMA() {}
+
 void CellularCapabilityUniversalCDMA::InitProxies() {
   SLOG(Cellular, 2) << __func__;
   modem_cdma_proxy_.reset(
@@ -78,10 +78,9 @@
   CellularCapabilityUniversal::ReleaseProxies();
 }
 
-void CellularCapabilityUniversalCDMA::Activate(
-    const string &carrier,
-    Error *error,
-    const ResultCallback &callback) {
+void CellularCapabilityUniversalCDMA::Activate(const string &carrier,
+                                               Error *error,
+                                               const ResultCallback &callback) {
   // Currently activation over the cellular network is not supported using
   // ModemManager-next. Service activation is currently carried through over
   // non-cellular networks and only the final step of the OTA activation