Add app entities widget for recently opened apps

If there is no recently opened app should be shown,
just show up an "All apps" preference.

If there are some recently opened apps, we show up
result with app entites controller.

- Clean up some useless ui. (category)
- User BasePreferenceController
- Modify test cases.

Test: robotest, visual
Change-Id: I411f61ed32eaaed97921941fd5026f1d65308d00
Fixes: 123538183

src/com/android/settings/applications/AppAndNotificationDashboardFragment.java

@@ -16,14 +16,10 @@
 
 package com.android.settings.applications;
 
-import android.app.Activity;
-import android.app.Application;
 import android.app.settings.SettingsEnums;
 import android.content.Context;
 import android.provider.SearchIndexableResource;
 
-import androidx.fragment.app.Fragment;
-
 import com.android.settings.R;
 import com.android.settings.dashboard.DashboardFragment;
 import com.android.settings.notification.EmergencyBroadcastPreferenceController;
@@ -63,27 +59,20 @@ public class AppAndNotificationDashboardFragment extends DashboardFragment {
     @Override
     public void onAttach(Context context) {
         super.onAttach(context);
+
         use(SpecialAppAccessPreferenceController.class).setSession(getSettingsLifecycle());
+        use(RecentAppsPreferenceController.class).setFragment(this /* fragment */);
     }
 
     @Override
     protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
-        final Activity activity = getActivity();
-        final Application app;
-        if (activity != null) {
-            app = activity.getApplication();
-        } else {
-            app = null;
-        }
-        return buildPreferenceControllers(context, app, this);
+        return buildPreferenceControllers(context);
     }
 
-    private static List<AbstractPreferenceController> buildPreferenceControllers(Context context,
-            Application app, Fragment host) {
+    private static List<AbstractPreferenceController> buildPreferenceControllers(Context context) {
         final List<AbstractPreferenceController> controllers = new ArrayList<>();
         controllers.add(new EmergencyBroadcastPreferenceController(context,
                 "app_and_notif_cell_broadcast_settings"));
-        controllers.add(new RecentAppsPreferenceController(context, app, host));
         return controllers;
     }
 
@@ -100,7 +89,7 @@ public class AppAndNotificationDashboardFragment extends DashboardFragment {
                 @Override
                 public List<AbstractPreferenceController> createPreferenceControllers(
                         Context context) {
-                    return buildPreferenceControllers(context, null, null /* host */);
+                    return buildPreferenceControllers(context);
                 }
             };
 }