Remove unneeded custom shadow of PowerManager

import android.content.Context;

import androidx.test.core.app.ApplicationProvider;

import com.android.settings.testutils.XmlTestUtils;

import com.android.settings.testutils.shadow.ShadowPowerManager;

import com.android.settingslib.core.AbstractPreferenceController;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.robolectric.RobolectricTestRunner;

import org.robolectric.RuntimeEnvironment;

import org.robolectric.annotation.Config;

import java.util.ArrayList;

import java.util.List;

public class DisplaySettingsTest {

    @Test

    @Config(shadows = ShadowPowerManager.class)

    public void testPreferenceControllers_getPreferenceKeys_existInPreferenceScreen() {

        final Context context = RuntimeEnvironment.application;

        final Context context = ApplicationProvider.getApplicationContext();

        final DisplaySettings fragment = new DisplaySettings();

        final List<String> preferenceScreenKeys = XmlTestUtils.getKeysFromPreferenceXml(context,

                fragment.getPreferenceScreenResId());

/*

 * Copyright (C) 2017 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 *

 */

package com.android.settings.testutils.shadow;

import android.os.PowerManager;

import org.robolectric.annotation.Implementation;

import org.robolectric.annotation.Implements;

@Implements(PowerManager.class)

public class ShadowPowerManager {

    @Implementation

    protected int getMinimumScreenBrightnessSetting() {

        return 0;

    }

    @Implementation

    protected int getMaximumScreenBrightnessSetting() {

        return 0;

    }

}