Add Transcode Settings screen in Developer Options

This screen would be used to enable/disable transcoding for all apps, and select a list of apps to be skipped from transcoding.
UI screenshot: https://screenshot.googleplex.com/4bpbZdM6vbhdw5u

Design doc reference for native transcoding: go/seamless-transcoding

Test: Manual
Bug: 169547037
Change-Id: I7cf72131560b99728083838bf0dad400bb5cb4a9

tests/robotests/src/com/android/settings/development/transcode/TranscodeGlobalTogglePreferenceControllerTest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2020 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.development.transcode;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.content.Context;
+import android.os.SystemProperties;
+
+import androidx.test.core.app.ApplicationProvider;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+
+@RunWith(RobolectricTestRunner.class)
+public class TranscodeGlobalTogglePreferenceControllerTest {
+
+    private static final String TRANSCODE_ENABLED_PROP_KEY = "persist.sys.fuse.transcode";
+
+    private TranscodeGlobalTogglePreferenceController mController;
+
+    @Before
+    public void setUp() {
+        Context context = ApplicationProvider.getApplicationContext();
+        mController = new TranscodeGlobalTogglePreferenceController(context, "test_key");
+    }
+
+    @Test
+    public void isAvailable_shouldReturnTrue() {
+        assertThat(mController.isAvailable()).isTrue();
+    }
+
+    @Test
+    public void isChecked_whenEnabled_shouldReturnTrue() {
+        SystemProperties.set(TRANSCODE_ENABLED_PROP_KEY, "true");
+        assertThat(mController.isChecked()).isTrue();
+    }
+
+    @Test
+    public void isChecked_whenDisabled_shouldReturnTrue() {
+        SystemProperties.set(TRANSCODE_ENABLED_PROP_KEY, "false");
+        assertThat(mController.isChecked()).isFalse();
+    }
+
+    @Test
+    public void setChecked_withTrue_shouldUpdateSystemProperty() {
+        // Simulate the UI being clicked.
+        mController.setChecked(true);
+
+        // Verify the system property was updated with the UI value.
+        assertThat(SystemProperties.getBoolean(TRANSCODE_ENABLED_PROP_KEY, false)).isTrue();
+    }
+
+    @Test
+    public void setChecked_withFalse_shouldUpdateSystemProperty() {
+        // Simulate the UI being clicked.
+        mController.setChecked(false);
+
+        // Verify the system property was updated with the UI value.
+        assertThat(SystemProperties.getBoolean(TRANSCODE_ENABLED_PROP_KEY, true)).isFalse();
+    }
+}

tests/robotests/src/com/android/settings/development/transcode/TranscodeSkipAppsPreferenceControllerTest.java

@@ -0,0 +1,155 @@
+/*
+ * Copyright (C) 2020 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.development.transcode;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.atLeastOnce;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.content.Intent;
+import android.content.pm.ActivityInfo;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
+import android.graphics.drawable.Drawable;
+import android.os.SystemProperties;
+
+import androidx.preference.Preference;
+import androidx.preference.PreferenceScreen;
+import androidx.preference.SwitchPreference;
+import androidx.test.core.app.ApplicationProvider;
+
+import com.android.settings.R;
+
+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;
+import org.robolectric.Shadows;
+import org.robolectric.shadows.ShadowPackageManager;
+
+import java.util.Collections;
+
+@RunWith(RobolectricTestRunner.class)
+public class TranscodeSkipAppsPreferenceControllerTest {
+
+    private static final int APPLICATION_UID = 1234;
+    private static final String SKIP_SELECTED_APPS_PROP_KEY =
+            "persist.sys.fuse.transcode_skip_uids";
+
+    @Mock
+    private PreferenceScreen mScreen;
+    private Context mContext;
+    private ShadowPackageManager mShadowPackageManager;
+    private TranscodeSkipAppsPreferenceController mController;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mContext = ApplicationProvider.getApplicationContext();
+        mShadowPackageManager = Shadows.shadowOf(mContext.getPackageManager());
+        mController = new TranscodeSkipAppsPreferenceController(mContext, "test_key");
+        Preference preference = new Preference(mContext);
+
+        when(mScreen.getContext()).thenReturn(mContext);
+        when(mScreen.findPreference(mController.getPreferenceKey())).thenReturn(preference);
+    }
+
+    @Test
+    public void isAlwaysAvailable() {
+        assertThat(mController.isAvailable()).isTrue();
+    }
+
+    @Test
+    public void display_hasLaunchAbleApps_shouldDisplay() {
+        Intent launcherIntent = new Intent(Intent.ACTION_MAIN);
+        launcherIntent.addCategory(Intent.CATEGORY_LAUNCHER);
+        final ResolveInfo resolveInfo = new FakeResolveInfo(mContext);
+        ApplicationInfo applicationInfo = new ApplicationInfo();
+        applicationInfo.uid = APPLICATION_UID;
+        ActivityInfo activityInfo = new ActivityInfo();
+        activityInfo.applicationInfo = applicationInfo;
+        resolveInfo.activityInfo = activityInfo;
+        mShadowPackageManager.setResolveInfosForIntent(launcherIntent,
+                Collections.singletonList(resolveInfo));
+
+        mController.displayPreference(mScreen);
+
+        verify(mScreen, atLeastOnce()).addPreference(any(Preference.class));
+    }
+
+    @Test
+    public void preferenceChecked_shouldSkipApp() {
+        // First ensure that the app is not in skip list.
+        SystemProperties.set(SKIP_SELECTED_APPS_PROP_KEY, String.valueOf(-1));
+        SwitchPreference switchPreference = createPreference(/* defaultCheckedState = */ false);
+
+        switchPreference.performClick();
+
+        // Verify that the app is added to skip list.
+        assertThat(SystemProperties.get(SKIP_SELECTED_APPS_PROP_KEY)).contains(
+                String.valueOf(APPLICATION_UID));
+    }
+
+    @Test
+    public void preferenceUnchecked_shouldNotSkipApp() {
+        // First ensure that the app is in skip list.
+        SystemProperties.set(SKIP_SELECTED_APPS_PROP_KEY, String.valueOf(APPLICATION_UID));
+        SwitchPreference switchPreference = createPreference(/* defaultCheckedState = */ true);
+
+        switchPreference.performClick();
+
+        // Verify that the app is removed from skip list.
+        assertThat(SystemProperties.get(SKIP_SELECTED_APPS_PROP_KEY)).doesNotContain(
+                String.valueOf(APPLICATION_UID));
+    }
+
+    private SwitchPreference createPreference(boolean defaultCheckedState) {
+        SwitchPreference preference = new SwitchPreference(mContext);
+        preference.setTitle("Test Pref");
+        preference.setIcon(R.drawable.ic_settings_24dp);
+        preference.setKey(String.valueOf(APPLICATION_UID));
+        preference.setChecked(defaultCheckedState);
+        preference.setOnPreferenceChangeListener(mController);
+        return preference;
+    }
+
+    private static class FakeResolveInfo extends ResolveInfo {
+
+        private final Context mContext;
+
+        FakeResolveInfo(Context context) {
+            this.mContext = context;
+        }
+
+        @Override
+        public CharSequence loadLabel(PackageManager pm) {
+            return "TestName";
+        }
+
+        @Override
+        public Drawable loadIcon(PackageManager pm) {
+            return mContext.getDrawable(R.drawable.ic_settings_24dp);
+        }
+    }
+}