Remove Numbering System preference if no corresponding locale.

- If locale has no multiple numbering systems, it shall not
   show the locale on list.
 - If there is no locale with numberung system, remove the entry of
   numbering system preference on UI.

Bug: b/274053189
Test: atest passed
Test: Manual test passed
Change-Id: If61c7e233630644e2d6245c5efd75d15d52cf94b

tests/unit/src/com/android/settings/regionalpreferences/NumberingSystemControllerTest.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import static com.android.settings.core.BasePreferenceController.AVAILABLE;
+import static com.android.settings.core.BasePreferenceController.CONDITIONALLY_UNAVAILABLE;
+
+import static org.junit.Assert.assertEquals;
+
+import android.content.Context;
+import android.os.LocaleList;
+
+import androidx.test.core.app.ApplicationProvider;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class NumberingSystemControllerTest {
+    private Context mApplicationContext;
+    private NumberingSystemController mController;
+
+    @Before
+    public void setUp() throws Exception {
+        mApplicationContext = ApplicationProvider.getApplicationContext();
+    }
+
+    @Test
+    public void getAvailabilityStatus_noLocale_unavailable() {
+        LocaleList.setDefault(LocaleList.forLanguageTags("en-US,zh-Hant-TW"));
+        mController = new NumberingSystemController(mApplicationContext, "key");
+
+        int result = mController.getAvailabilityStatus();
+
+        assertEquals(CONDITIONALLY_UNAVAILABLE, result);
+    }
+
+    @Test
+    public void getAvailabilityStatus_hasLocaleWithNumberingSystems_available() {
+        // ar-JO has different numbering system.
+        LocaleList.setDefault(LocaleList.forLanguageTags("en-US,zh-Hant-TW,ar-JO"));
+        mController = new NumberingSystemController(mApplicationContext, "key");
+
+        int result = mController.getAvailabilityStatus();
+
+        assertEquals(AVAILABLE, result);
+    }
+}