Clean up DarkUIInfoDialogFragment

The usage of this dialog is removed in
Change Ie2cf147de53385ae0c626c8472306f1b85317686

But this dialog is created (but not show) in DarkUIPreferenceController
each time dark mode toggle is turned on by user.

So clean this up.

Fix: 234419979
Test: make Settings
Change-Id: Icdc9d7a4fb77dc8b2a3f1a9d8e3f40fc0af4917d

src/com/android/settings/display/DarkUIPreferenceController.java

@@ -23,10 +23,8 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.res.Configuration;
 import android.os.PowerManager;
-import android.provider.Settings;
 
 import androidx.annotation.VisibleForTesting;
-import androidx.fragment.app.Fragment;
 import androidx.preference.Preference;
 import androidx.preference.PreferenceScreen;
 
@@ -39,7 +37,6 @@ import com.android.settingslib.core.lifecycle.events.OnStop;
 public class DarkUIPreferenceController extends TogglePreferenceController implements
         LifecycleObserver, OnStart, OnStop {
 
-    public static final String DARK_MODE_PREFS = "dark_mode_prefs";
     public static final String PREF_DARK_MODE_DIALOG_SEEN = "dark_mode_dialog_seen";
     public static final int DIALOG_SEEN = 1;
 
@@ -48,9 +45,6 @@ public class DarkUIPreferenceController extends TogglePreferenceController imple
 
     private UiModeManager mUiModeManager;
     private PowerManager mPowerManager;
-    private Context mContext;
-
-    private Fragment mFragment;
 
     private BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
@@ -61,7 +55,6 @@ public class DarkUIPreferenceController extends TogglePreferenceController imple
 
     public DarkUIPreferenceController(Context context, String key) {
         super(context, key);
-        mContext = context;
         mUiModeManager = context.getSystemService(UiModeManager.class);
         mPowerManager = context.getSystemService(PowerManager.class);
     }
@@ -86,12 +79,6 @@ public class DarkUIPreferenceController extends TogglePreferenceController imple
 
     @Override
     public boolean setChecked(boolean isChecked) {
-        final boolean dialogSeen =
-                Settings.Secure.getInt(mContext.getContentResolver(),
-                        Settings.Secure.DARK_MODE_DIALOG_SEEN, 0) == DIALOG_SEEN;
-        if (!dialogSeen && isChecked) {
-            showDarkModeDialog();
-        }
         return mUiModeManager.setNightModeActivated(isChecked);
     }
 
@@ -100,13 +87,6 @@ public class DarkUIPreferenceController extends TogglePreferenceController imple
         return R.string.menu_key_display;
     }
 
-    private void showDarkModeDialog() {
-        final DarkUIInfoDialogFragment frag = new DarkUIInfoDialogFragment();
-        if (mFragment != null && mFragment.getFragmentManager() != null) {
-            frag.show(mFragment.getFragmentManager(), getClass().getName());
-        }
-    }
-
     @VisibleForTesting
     void updateEnabledStateIfNeeded() {
         if (mPreference == null) {
@@ -133,11 +113,6 @@ public class DarkUIPreferenceController extends TogglePreferenceController imple
                 new IntentFilter(PowerManager.ACTION_POWER_SAVE_MODE_CHANGED));
     }
 
-    // used by AccessibilitySettings
-    public void setParentFragment(Fragment fragment) {
-        mFragment = fragment;
-    }
-
     @Override
     public void onStop() {
         mContext.unregisterReceiver(mReceiver);