Fix the toggle button flicker problem when display

- Root cause: the side effect of the parallel controller loading.
- Solution: disable the parallel approach and remove the entry point
  of parallel approach in DashboardFragment.

Fixes: 187838753
Test: Robo test for AppInfoDashboardFragment, ConfigureNotificationSettings,
      ConnectedDeviceDashboardFragment, DevelopmentSettingsDashboardFragment,
      NetworkDashboardFragment, DashboardFragment
Change-Id: If3b09c4fd6f33042e0ed38704f08e855ab8f5377

src/com/android/settings/applications/appinfo/AppInfoDashboardFragment.java

@@ -309,11 +309,6 @@ public class AppInfoDashboardFragment extends DashboardFragment
         return controllers;
     }
 
-    @Override
-    protected boolean isParalleledControllers() {
-        return true;
-    }
-
     void addToCallbackList(Callback callback) {
         if (callback != null) {
             mCallbacks.add(callback);

src/com/android/settings/connecteddevice/ConnectedDeviceDashboardFragment.java

@@ -49,11 +49,6 @@ public class ConnectedDeviceDashboardFragment extends DashboardFragment {
         return TAG;
     }
 
-    @Override
-    protected boolean isParalleledControllers() {
-        return true;
-    }
-
     @Override
     public int getHelpResource() {
         return R.string.help_url_connected_devices;

src/com/android/settings/dashboard/DashboardFragment.java

@@ -22,7 +22,6 @@ import android.content.Context;
 import android.os.Bundle;
 import android.text.TextUtils;
 import android.util.ArrayMap;
-import android.util.FeatureFlagUtils;
 import android.util.Log;
 
 import androidx.annotation.CallSuper;
@@ -36,7 +35,6 @@ import androidx.preference.SwitchPreference;
 import com.android.settings.R;
 import com.android.settings.SettingsPreferenceFragment;
 import com.android.settings.core.BasePreferenceController;
-import com.android.settings.core.FeatureFlags;
 import com.android.settings.core.PreferenceControllerListHelper;
 import com.android.settings.core.SettingsBaseActivity;
 import com.android.settings.overlay.FeatureFactory;
@@ -360,11 +358,6 @@ public abstract class DashboardFragment extends SettingsPreferenceFragment
      * Update state of each preference managed by PreferenceController.
      */
     protected void updatePreferenceStates() {
-        if (isParalleledControllers() && FeatureFlagUtils.isEnabled(getContext(),
-                FeatureFlags.CONTROLLER_ENHANCEMENT)) {
-            updatePreferenceStatesInParallel();
-            return;
-        }
         final PreferenceScreen screen = getPreferenceScreen();
         Collection<List<AbstractPreferenceController>> controllerLists =
                 mPreferenceControllers.values();
@@ -396,6 +389,8 @@ public abstract class DashboardFragment extends SettingsPreferenceFragment
      * Use parallel method to update state of each preference managed by PreferenceController.
      */
     @VisibleForTesting
+    // To use this parallel approach will cause the side effect of the UI flicker. Such as
+    // the thumb sliding of the toggle button.
     void updatePreferenceStatesInParallel() {
         final PreferenceScreen screen = getPreferenceScreen();
         final Collection<List<AbstractPreferenceController>> controllerLists =

src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java

@@ -402,11 +402,6 @@ public class DevelopmentSettingsDashboardFragment extends RestrictedDashboardFra
         return mPreferenceControllers;
     }
 
-    @Override
-    protected boolean isParalleledControllers() {
-        return true;
-    }
-
     private void registerReceivers() {
         LocalBroadcastManager.getInstance(getContext())
                 .registerReceiver(mEnableAdbReceiver, new IntentFilter(

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

@@ -95,11 +95,6 @@ public class NetworkDashboardFragment extends DashboardFragment implements
                 this /* fragment */, this /* mobilePlanHost */);
     }
 
-    @Override
-    protected boolean isParalleledControllers() {
-        return true;
-    }
-
     private static List<AbstractPreferenceController> buildPreferenceControllers(Context context,
             Lifecycle lifecycle, MetricsFeatureProvider metricsFeatureProvider, Fragment fragment,
             MobilePlanPreferenceHost mobilePlanHost) {

src/com/android/settings/notification/ConfigureNotificationSettings.java

@@ -96,11 +96,6 @@ public class ConfigureNotificationSettings extends DashboardFragment implements
         mNotificationAssistantPreferenceController.setBackend(new NotificationBackend());
     }
 
-    @Override
-    protected boolean isParalleledControllers() {
-        return true;
-    }
-
     private static List<AbstractPreferenceController> buildPreferenceControllers(Context context,
             Application app, Fragment host) {
         final List<AbstractPreferenceController> controllers = new ArrayList<>();

tests/robotests/src/com/android/settings/dashboard/DashboardFragmentTest.java

@@ -37,7 +37,6 @@ import android.content.pm.ActivityInfo;
 import android.content.pm.ProviderInfo;
 import android.net.Uri;
 import android.os.Bundle;
-import android.util.FeatureFlagUtils;
 
 import androidx.preference.Preference;
 import androidx.preference.PreferenceFragmentCompat;
@@ -46,7 +45,6 @@ import androidx.preference.PreferenceScreen;
 import androidx.preference.SwitchPreference;
 
 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
-import com.android.settings.core.FeatureFlags;
 import com.android.settings.core.PreferenceControllerMixin;
 import com.android.settings.slices.BlockingSlicePrefController;
 import com.android.settings.testutils.FakeFeatureFactory;
@@ -335,37 +333,6 @@ public class DashboardFragmentTest {
         assertThat(pref).isInstanceOf(PrimarySwitchPreference.class);
     }
 
-    @Test
-    public void isFeatureFlagAndIsParalleled_runParalleledUpdatePreferenceStates() {
-        FeatureFlagUtils.setEnabled(mContext, FeatureFlags.CONTROLLER_ENHANCEMENT, true);
-        final TestFragment testFragment = spy(new TestFragment(RuntimeEnvironment.application));
-
-        testFragment.updatePreferenceStates();
-
-        verify(testFragment).updatePreferenceStatesInParallel();
-    }
-
-    @Test
-    public void notFeatureFlagAndIsParalleled_notRunParalleledUpdatePreferenceStates() {
-        FeatureFlagUtils.setEnabled(mContext, FeatureFlags.CONTROLLER_ENHANCEMENT, false);
-        final TestFragment testFragment = spy(new TestFragment(RuntimeEnvironment.application));
-
-        testFragment.updatePreferenceStates();
-
-        verify(testFragment, never()).updatePreferenceStatesInParallel();
-    }
-
-    @Test
-    public void isFeatureFlagAndNotParalleled_notRunParalleledUpdatePreferenceStates() {
-        FeatureFlagUtils.setEnabled(mContext, FeatureFlags.CONTROLLER_ENHANCEMENT, true);
-        final TestFragment testFragment = spy(new TestFragment(RuntimeEnvironment.application));
-        testFragment.setUsingControllerEnhancement(false);
-
-        testFragment.updatePreferenceStates();
-
-        verify(testFragment, never()).updatePreferenceStatesInParallel();
-    }
-
     public static class TestPreferenceController extends AbstractPreferenceController
             implements PreferenceControllerMixin {