Revert "[Settings] Support getSystemService(Class<T>)"

This reverts commit d5ccde31a8.

Reason for revert: failure on test cases

Change-Id: I0a179a6ebb5ef1dec566ce6e8facd5f3b82d7c8a

src/com/android/settings/wifi/WifiWakeupPreferenceController.java

@@ -73,7 +73,7 @@ public class WifiWakeupPreferenceController extends TogglePreferenceController i
 
     public WifiWakeupPreferenceController(Context context) {
         super(context, KEY_ENABLE_WIFI_WAKEUP);
-        mLocationManager = context.getSystemService(LocationManager.class);
+        mLocationManager = (LocationManager) context.getSystemService(Service.LOCATION_SERVICE);
         mWifiManager = context.getSystemService(WifiManager.class);
     }