Add icon in RestrictedAppDetails

use preference_app to make sure the app icon is 24dp.

Bug: 71502850
Test: Screenshot | RunSettingsRoboTests
Change-Id: I0d7704246299201e72b991f199f9ddd2f224a8a3

tests/robotests/src/com/android/settings/widget/AppCheckBoxPreferenceTest.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2018 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.widget;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.content.Context;
+
+import com.android.settings.R;
+import com.android.settings.TestConfig;
+import com.android.settings.testutils.SettingsRobolectricTestRunner;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RuntimeEnvironment;
+import org.robolectric.annotation.Config;
+
+@RunWith(SettingsRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
+public class AppCheckBoxPreferenceTest {
+
+    private Context mContext;
+    private AppCheckBoxPreference mPreference;
+    private AppCheckBoxPreference mAttrPreference;
+
+    @Before
+    public void setUp() {
+        mContext = RuntimeEnvironment.application;
+        mPreference = new AppCheckBoxPreference(mContext);
+        mAttrPreference = new AppCheckBoxPreference(mContext, null /* attrs */);
+    }
+
+    @Test
+    public void testGetLayoutResource() {
+        assertThat(mPreference.getLayoutResource()).isEqualTo(R.layout.preference_app);
+        assertThat(mAttrPreference.getLayoutResource()).isEqualTo(R.layout.preference_app);
+    }
+}