Make some existing slices public.

Only PreferenceControllers with isPublicSlice() set to true are exposed
to other apps. Others will be Settings only.

Bug: 141088937
Test: robotests
Change-Id: I5934e89bc1b268fdd44acd630621fa46987728ff

tests/robotests/src/com/android/settings/nfc/SecureNfcPreferenceControllerTest.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2019 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.nfc;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.content.Context;
+
+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 SecureNfcPreferenceControllerTest {
+
+    private Context mContext;
+    private SecureNfcPreferenceController mController;
+
+    @Before
+    public void setUp() {
+        mContext = RuntimeEnvironment.application;
+        mController = new SecureNfcPreferenceController(mContext, "nfc_secure_settings");
+    }
+
+    @Test
+    public void isPublicSlice_returnsTrue() {
+        assertThat(mController.isPublicSlice()).isTrue();
+    }
+}