Add a setting to turn clipboard access notifications on/off.

This adds a new switch setting under Privacy to control whether
toast notifications are shown when an app accesses clipboard
(see b/179667029 for the clipboard access notification feature).

Bug: 179667029
Test: make RunSettingsRoboTests ROBOTEST_FILTER=
"com.android.settings.privacy.ShowClipAccessNotificationPreferenceControllerTest"

Change-Id: Ibac7f31538ab3e4d2ec476cb8c05cbbd0c7e6d41

tests/robotests/src/com/android/settings/privacy/ShowClipAccessNotificationPreferenceControllerTest.java

@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2021 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.privacy;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.provider.Settings;
+import android.provider.Settings.SettingNotFoundException;
+
+import androidx.preference.Preference;
+import androidx.preference.PreferenceScreen;
+import androidx.test.core.app.ApplicationProvider;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RobolectricTestRunner;
+
+@RunWith(RobolectricTestRunner.class)
+public class ShowClipAccessNotificationPreferenceControllerTest {
+
+    @Mock
+    private PreferenceScreen mScreen;
+
+    private Context mContext;
+    private ShowClipAccessNotificationPreferenceController mController;
+    private Preference mPreference;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mContext = ApplicationProvider.getApplicationContext();
+        mController = new ShowClipAccessNotificationPreferenceController(mContext);
+        mPreference = new Preference(mContext);
+        mPreference.setKey(mController.getPreferenceKey());
+    }
+
+    @Test
+    public void isChecked_settingIsOff_shouldReturnFalse() throws Exception {
+        setProperty(0);
+
+        assertThat(mController.isChecked()).isFalse();
+    }
+
+    @Test
+    public void isChecked_settingIsOn_shouldReturnTrue() throws Exception {
+        setProperty(1);
+
+        assertThat(mController.isChecked()).isTrue();
+    }
+
+    @Test
+    public void onPreferenceChange_turnOn_shouldChangeSettingTo1() throws Exception {
+        setProperty(0);
+
+        mController.onPreferenceChange(mPreference, true);
+
+        assertThat(mController.isChecked()).isTrue();
+        assertProperty(1);
+    }
+
+    @Test
+    public void onPreferenceChange_turnOff_shouldChangeSettingTo0() throws Exception {
+        setProperty(1);
+
+        mController.onPreferenceChange(mPreference, false);
+
+        assertThat(mController.isChecked()).isFalse();
+        assertProperty(0);
+    }
+
+    private void setProperty(int newValue) {
+        final ContentResolver contentResolver = mContext.getContentResolver();
+        Settings.Secure.putInt(
+                contentResolver, Settings.Secure.CLIPBOARD_SHOW_ACCESS_NOTIFICATIONS, newValue);
+    }
+
+    private void assertProperty(int expectedValue) throws SettingNotFoundException {
+        final ContentResolver contentResolver = mContext.getContentResolver();
+        assertThat(Settings.Secure.getInt(
+                contentResolver, Settings.Secure.CLIPBOARD_SHOW_ACCESS_NOTIFICATIONS))
+                .isEqualTo(expectedValue);
+    }
+}