[Provider Model] Internet Picker implementation.

Show mobile network on internet page

 With mobile network
  - https://screenshot.googleplex.com/7HzGhnbpitErynY

 Without mobile network
  - https://screenshot.googleplex.com/8sNVggTpKEhKeRh

Class diff: https://diff.googleplex.com/#key=WosyTF0ANVMf

Doc: https://docs.google.com/presentation/d/1azrZVS54pxM2lt9LkZHtFh_6W3fyDw_kTTPVQ_mJCi4/edit#slide=id.g9c7123c172_0_448

Bug: 173105859
Test: atest NetworkMobileProviderControllerTest passed
Test: make RunSettingsRoboTests ROBOTEST_FILTER=SubscriptionsPreferenceControllerTest passed

Change-Id: I9671a0b85aad1dd2f53772539505b0ad96edbda3

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

@@ -207,6 +207,12 @@ public class NetworkProviderSettings extends RestrictedSettingsFragment
     DataUsagePreference mDataUsagePreference;
     private LinkablePreference mStatusMessagePreference;
 
+    /**
+     * Mobile networks list for provider model
+     */
+    private static final String PREF_KEY_PROVIDER_MOBILE_NETWORK = "provider_model_mobile_network";
+    private NetworkMobileProviderController mNetworkMobileProviderController;
+
     /**
      * Tracks whether the user initiated a connection via clicking in order to autoscroll to the
      * network once connected.
@@ -255,6 +261,8 @@ public class NetworkProviderSettings extends RestrictedSettingsFragment
         mDataUsagePreference.setTemplate(NetworkTemplate.buildTemplateWifiWildcard(),
                 0 /*subId*/,
                 null /*service*/);
+        mNetworkMobileProviderController.init(getSettingsLifecycle());
+        mNetworkMobileProviderController.displayPreference(getPreferenceScreen());
     }
 
     @Override
@@ -340,6 +348,13 @@ public class NetworkProviderSettings extends RestrictedSettingsFragment
         }
     }
 
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+        mNetworkMobileProviderController =
+                new NetworkMobileProviderController(context, PREF_KEY_PROVIDER_MOBILE_NETWORK);
+    }
+
     @Override
     public void onDestroyView() {
         mWorkerThread.quit();