[Wi-Fi] Add STA+AP information in Hotspot & tethering footer

Use WifiManager#isStaApConcurrencySupported() to check if a
device supports STA+AP and shows the footer information.

Bug: 121328949
Test: make RunSettingsRoboTests ROBOTEST_FILTER=TetherSettingsTest
      make RunSettingsRoboTests ROBOTEST_FILTER=WifiTetherFooterPreferenceControllerTest
Change-Id: I3446abb5cc9cdf76da8d17f5de31bd65715c165c

tests/robotests/src/com/android/settings/wifi/tether/WifiTetherFooterPreferenceControllerTest.java

@@ -0,0 +1,87 @@
+/*
+ * 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.wifi.tether;
+
+import static org.mockito.ArgumentMatchers.anyString;;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.wifi.WifiManager;
+
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.R;
+import com.android.settingslib.widget.FooterPreference;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Answers;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RobolectricTestRunner;
+
+@RunWith(RobolectricTestRunner.class)
+public class WifiTetherFooterPreferenceControllerTest {
+    @Mock(answer = Answers.RETURNS_DEEP_STUBS)
+    private Context mContext;
+    @Mock
+    private ConnectivityManager mConnectivityManager;
+    @Mock
+    private WifiManager mWifiManager;
+    @Mock
+    private PreferenceScreen mScreen;
+    @Mock
+    private FooterPreference mPreference;
+
+    private WifiTetherFooterPreferenceController mController;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+
+        when(mContext.getSystemService(Context.WIFI_SERVICE)).thenReturn(mWifiManager);
+        when(mContext.getSystemService(Context.CONNECTIVITY_SERVICE))
+                .thenReturn(mConnectivityManager);
+        when(mConnectivityManager.getTetherableWifiRegexs()).thenReturn(new String[]{"1", "2"});
+        mController = new WifiTetherFooterPreferenceController(mContext);
+        when(mScreen.findPreference(anyString())).thenReturn(mPreference);
+    }
+
+    @Test
+    public void displayPreference_supportStaAp_showConcurrentInfo() {
+        when(mWifiManager.isStaApConcurrencySupported()).thenReturn(true);
+
+        mController.displayPreference(mScreen);
+
+        verify(mPreference, never()).setTitle(R.string.tethering_footer_info);
+        verify(mPreference).setTitle(R.string.tethering_footer_info_sta_ap_concurrency);
+    }
+
+    @Test
+    public void displayPreference_notSupportStaAp_showNotConcurrentInfo() {
+        when(mWifiManager.isStaApConcurrencySupported()).thenReturn(false);
+
+        mController.displayPreference(mScreen);
+
+        verify(mPreference).setTitle(R.string.tethering_footer_info);
+        verify(mPreference, never()).setTitle(R.string.tethering_footer_info_sta_ap_concurrency);
+    }
+}