Deprecate AppListPreference and AppListPrefWithSettings

- Convert ManageAssist into DashboardFragment
- Convert default assist pref to DefaultAppPickerFragment
- Add PreferenceController for each pref
- Add tests

Bug: 35203386
Test: make RunSettingsRoboTests

Change-Id: I0350a06cae7457809fb261e2d8ec99eda80cc50a
diff --git a/src/com/android/settings/search/SearchIndexableResources.java b/src/com/android/settings/search/SearchIndexableResources.java
index 700ab72..6688b99 100644
--- a/src/com/android/settings/search/SearchIndexableResources.java
+++ b/src/com/android/settings/search/SearchIndexableResources.java
@@ -37,6 +37,7 @@
 import com.android.settings.applications.AdvancedAppSettings;
 import com.android.settings.applications.AppAndNotificationDashboardFragment;
 import com.android.settings.applications.SpecialAccessSettings;
+import com.android.settings.applications.assist.ManageAssist;
 import com.android.settings.backup.BackupSettingsFragment;
 import com.android.settings.bluetooth.BluetoothSettings;
 import com.android.settings.connecteddevice.ConnectedDeviceDashboardFragment;
@@ -133,6 +134,7 @@
         addIndex(BatterySaverSettings.class,
                 R.xml.battery_saver_settings, R.drawable.ic_settings_battery);
         addIndex(AdvancedAppSettings.class, NO_DATA_RES_ID, R.drawable.ic_settings_applications);
+        addIndex(ManageAssist.class, NO_DATA_RES_ID, R.drawable.ic_settings_applications);
         addIndex(SpecialAccessSettings.class,
                 R.xml.special_access, R.drawable.ic_settings_applications);
         addIndex(UserSettings.class, NO_DATA_RES_ID, R.drawable.ic_settings_multiuser);