Refactor airplane mode preference controller.

- Convert inheritance from AbstractPreferenceController to
TogglePreferenceController.
- Register AirplaneModePreferenceController in XML.
- Decouple AirplaneModeEnabler with preference, leave the UI be
controled by PreferenceController.
- Add RoboTests test cases for AirplaneModePreferenceController.

Fixes: 67997339
Test: RunSettingsRoboTests
Change-Id: I7398943ed51345e014ee7aa774bfae1ca28632f1

src/com/android/settings/network/NetworkDashboardFragment.java

@@ -71,6 +71,8 @@ public class NetworkDashboardFragment extends DashboardFragment implements
     public void onAttach(Context context) {
         super.onAttach(context);
         mNetworkResetController = new NetworkResetActionMenuController(context, MENU_NETWORK_RESET);
+
+        use(AirplaneModePreferenceController.class).setFragment(this);
     }
 
     @Override
@@ -94,8 +96,6 @@ public class NetworkDashboardFragment extends DashboardFragment implements
     private static List<AbstractPreferenceController> buildPreferenceControllers(Context context,
             Lifecycle lifecycle, MetricsFeatureProvider metricsFeatureProvider, Fragment fragment,
             MobilePlanPreferenceHost mobilePlanHost) {
-        final AirplaneModePreferenceController airplaneModePreferenceController =
-                new AirplaneModePreferenceController(context, fragment);
         final MobilePlanPreferenceController mobilePlanPreferenceController =
                 new MobilePlanPreferenceController(context, mobilePlanHost);
         final WifiMasterSwitchPreferenceController wifiPreferenceController =
@@ -108,7 +108,6 @@ public class NetworkDashboardFragment extends DashboardFragment implements
                 new PrivateDnsPreferenceController(context);
 
         if (lifecycle != null) {
-            lifecycle.addObserver(airplaneModePreferenceController);
             lifecycle.addObserver(mobilePlanPreferenceController);
             lifecycle.addObserver(wifiPreferenceController);
             lifecycle.addObserver(mobileNetworkPreferenceController);
@@ -117,7 +116,6 @@ public class NetworkDashboardFragment extends DashboardFragment implements
         }
 
         final List<AbstractPreferenceController> controllers = new ArrayList<>();
-        controllers.add(airplaneModePreferenceController);
         controllers.add(mobileNetworkPreferenceController);
         controllers.add(new TetherPreferenceController(context, lifecycle));
         controllers.add(vpnPreferenceController);