Create preference to allow user to toggle sticky battery saver

This adds the toggle that makes it so that battery saver turns
off automatically at high battery percentages or not.

Test: robotests
Bug: 112232746
Change-Id: I0df879a43e5390bc671c47e780bbbb466a3e9353

tests/robotests/src/com/android/settings/fuelgauge/batterysaver/BatterySaverStickyPreferenceControllerTest.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2016 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.batterysaver;
+
+import static com.android.settings.fuelgauge.batterysaver.BatterySaverStickyPreferenceController.LOW_POWER_STICKY_AUTO_DISABLE_ENABLED;
+import static com.google.common.truth.Truth.assertThat;
+
+import android.content.Context;
+import android.provider.Settings;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.RuntimeEnvironment;
+
+@RunWith(RobolectricTestRunner.class)
+public class BatterySaverStickyPreferenceControllerTest {
+
+    private static final String PREF_KEY = "battery_saver_sticky";
+
+    private Context mContext;
+    private BatterySaverStickyPreferenceController mController;
+
+    @Before
+    public void setup() {
+        mContext = RuntimeEnvironment.application;
+        mController = new BatterySaverStickyPreferenceController(mContext, PREF_KEY);
+    }
+
+    private int getAutoDisableSetting() {
+        return Settings.System.getInt(mContext.getContentResolver(),
+                LOW_POWER_STICKY_AUTO_DISABLE_ENABLED,
+                1);
+    }
+
+    @Test
+    public void testOnPreferenceChange_turnOnKeepActive_autoDisableOff() {
+        mController.onPreferenceChange(null, true);
+        final int isOn = getAutoDisableSetting();
+        assertThat(isOn).isEqualTo(0);
+    }
+
+    @Test
+    public void testOnPreferenceChange_TurnOffKeepActive_autoDisableOff() {
+        mController.onPreferenceChange(null, false);
+        final int isOn = getAutoDisableSetting();
+        assertThat(isOn).isEqualTo(1);
+    }
+}