Making "Battery Saver" use MasterSwitchPreference.

By using MasterSwitchPreference, we make "battery saver" to have
two parts: left part is the clickable summary jumping to other
fragment while right part is a switch toggle.

Also remove the previous battery saver preference.

Bug: 34279051
Test: RunSettingsRoboTests

Change-Id: If36fa9741e413a9bbdd57fa67a2c15b6e457afd7

tests/robotests/src/com/android/settings/fuelgauge/BatterySaverControllerTest.java

@@ -0,0 +1,94 @@
+/*
+ * 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.fuelgauge;
+
+import android.content.Context;
+import android.os.PowerManager;
+import com.android.settings.SettingsRobolectricTestRunner;
+import com.android.settings.TestConfig;
+import com.android.settings.core.lifecycle.Lifecycle;
+import com.android.settings.widget.MasterSwitchPreference;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.annotation.Config;
+import org.robolectric.util.ReflectionHelpers;
+
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@RunWith(SettingsRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
+public class BatterySaverControllerTest {
+    @Mock
+    private MasterSwitchPreference mBatterySaverPref;
+    @Mock
+    private PowerManager mPowerManager;
+    @Mock
+    private Context mContext;
+    @Mock
+    private Lifecycle mLifecycle;
+    private BatterySaverController mBatterySaverController;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+
+        mBatterySaverController = spy(new BatterySaverController(mContext, mLifecycle));
+        ReflectionHelpers.setField(mBatterySaverController, "mPowerManager", mPowerManager);
+        ReflectionHelpers.setField(mBatterySaverController, "mBatterySaverPref", mBatterySaverPref);
+        doNothing().when(mBatterySaverController).refreshConditionManager();
+    }
+
+    @Test
+    public void testOnPreferenceChange_TurnOnBatterySaver_BatterySaverOn() {
+        testOnPreferenceChangeInner(true);
+    }
+
+    @Test
+    public void testOnPreferenceChange_TurnOffBatterySaver_BatterySaverOff() {
+        testOnPreferenceChangeInner(false);
+    }
+
+    @Test
+    public void testUpdateState_SaverModeOn_PreferenceChecked() {
+        testUpdateStateInner(true);
+    }
+
+    @Test
+    public void testUpdateState_SaverModeOff_PreferenceUnChecked() {
+        testUpdateStateInner(false);
+    }
+
+    private void testOnPreferenceChangeInner(final boolean saverOn) {
+        when(mPowerManager.setPowerSaveMode(saverOn)).thenReturn(true);
+        when(mPowerManager.isPowerSaveMode()).thenReturn(!saverOn);
+
+        mBatterySaverController.onPreferenceChange(mBatterySaverPref, saverOn);
+        verify(mPowerManager).setPowerSaveMode(saverOn);
+    }
+
+    private void testUpdateStateInner(final boolean saverOn) {
+        when(mPowerManager.isPowerSaveMode()).thenReturn(saverOn);
+
+        mBatterySaverController.updateState(mBatterySaverPref);
+        verify(mBatterySaverPref).setChecked(saverOn);
+    }
+}