Use alternative PhoneStateListener formal API

MultinetworkPolicyTracker is part of Connectivity mainline module
which cannot call @hide API to register PhoneStateListener. Thus,
replace it to formal API.

Bug: 171183530
Test: atest FrameworksNetTests
Change-Id: Ib02790623e82726aaada33f559226020d1e0019b
diff --git a/framework/src/android/net/util/MultinetworkPolicyTracker.java b/framework/src/android/net/util/MultinetworkPolicyTracker.java
index 85e3fa3..43fffd7 100644
--- a/framework/src/android/net/util/MultinetworkPolicyTracker.java
+++ b/framework/src/android/net/util/MultinetworkPolicyTracker.java
@@ -40,6 +40,8 @@
 
 import java.util.Arrays;
 import java.util.List;
+import java.util.concurrent.Executor;
+import java.util.concurrent.RejectedExecutionException;
 
 /**
  * A class to encapsulate management of the "Smart Networking" capability of
@@ -73,6 +75,32 @@
     private volatile int mMeteredMultipathPreference;
     private int mActiveSubId = SubscriptionManager.INVALID_SUBSCRIPTION_ID;
 
+    // Mainline module can't use internal HandlerExecutor, so add an identical executor here.
+    private static class HandlerExecutor implements Executor {
+        @NonNull
+        private final Handler mHandler;
+
+        HandlerExecutor(@NonNull Handler handler) {
+            mHandler = handler;
+        }
+        @Override
+        public void execute(Runnable command) {
+            if (!mHandler.post(command)) {
+                throw new RejectedExecutionException(mHandler + " is shutting down");
+            }
+        }
+    }
+
+    @VisibleForTesting
+    protected class ActiveDataSubscriptionIdChangedListener extends PhoneStateListener
+            implements PhoneStateListener.ActiveDataSubscriptionIdChangedListener {
+        @Override
+        public void onActiveDataSubscriptionIdChanged(int subId) {
+            mActiveSubId = subId;
+            reevaluateInternal();
+        }
+    }
+
     public MultinetworkPolicyTracker(Context ctx, Handler handler) {
         this(ctx, handler, null);
     }
@@ -93,14 +121,8 @@
             }
         };
 
-        ctx.getSystemService(TelephonyManager.class).listen(
-                new PhoneStateListener(handler.getLooper()) {
-            @Override
-            public void onActiveDataSubscriptionIdChanged(int subId) {
-                mActiveSubId = subId;
-                reevaluateInternal();
-            }
-        }, PhoneStateListener.LISTEN_ACTIVE_DATA_SUBSCRIPTION_ID_CHANGE);
+        ctx.getSystemService(TelephonyManager.class).registerPhoneStateListener(
+                new HandlerExecutor(handler), new ActiveDataSubscriptionIdChangedListener());
 
         updateAvoidBadWifi();
         updateMeteredMultipathPreference();
diff --git a/tests/net/java/android/net/util/MultinetworkPolicyTrackerTest.kt b/tests/net/java/android/net/util/MultinetworkPolicyTrackerTest.kt
new file mode 100644
index 0000000..9b0cfa9
--- /dev/null
+++ b/tests/net/java/android/net/util/MultinetworkPolicyTrackerTest.kt
@@ -0,0 +1,137 @@
+/*
+ * Copyright (C) 2021 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 android.net.util
+
+import android.content.Context
+import android.content.res.Resources
+import android.net.ConnectivityManager.MULTIPATH_PREFERENCE_HANDOVER
+import android.net.ConnectivityManager.MULTIPATH_PREFERENCE_PERFORMANCE
+import android.net.ConnectivityManager.MULTIPATH_PREFERENCE_RELIABILITY
+import android.net.util.MultinetworkPolicyTracker.ActiveDataSubscriptionIdChangedListener
+import android.provider.Settings
+import android.provider.Settings.Global.NETWORK_AVOID_BAD_WIFI
+import android.provider.Settings.Global.NETWORK_METERED_MULTIPATH_PREFERENCE
+import android.telephony.SubscriptionInfo
+import android.telephony.SubscriptionManager
+import android.telephony.TelephonyManager
+import android.test.mock.MockContentResolver
+import androidx.test.filters.SmallTest
+import androidx.test.runner.AndroidJUnit4
+import com.android.internal.R
+import com.android.internal.util.test.FakeSettingsProvider
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.ArgumentCaptor
+import org.mockito.ArgumentMatchers.anyInt
+import org.mockito.ArgumentMatchers.argThat
+import org.mockito.Mockito.any
+import org.mockito.Mockito.doReturn
+import org.mockito.Mockito.mock
+import org.mockito.Mockito.times
+import org.mockito.Mockito.verify
+
+/**
+ * Tests for [MultinetworkPolicyTracker].
+ *
+ * Build, install and run with:
+ * atest android.net.util.MultinetworkPolicyTrackerTest
+ */
+@RunWith(AndroidJUnit4::class)
+@SmallTest
+class MultinetworkPolicyTrackerTest {
+    private val resources = mock(Resources::class.java).also {
+        doReturn(0).`when`(it).getInteger(R.integer.config_networkAvoidBadWifi)
+    }
+    private val telephonyManager = mock(TelephonyManager::class.java)
+    private val subscriptionManager = mock(SubscriptionManager::class.java).also {
+        doReturn(null).`when`(it).getActiveSubscriptionInfo(anyInt())
+    }
+    private val resolver = MockContentResolver().apply {
+        addProvider(Settings.AUTHORITY, FakeSettingsProvider()) }
+    private val context = mock(Context::class.java).also {
+        doReturn(Context.TELEPHONY_SERVICE).`when`(it)
+                .getSystemServiceName(TelephonyManager::class.java)
+        doReturn(telephonyManager).`when`(it).getSystemService(Context.TELEPHONY_SERVICE)
+        doReturn(subscriptionManager).`when`(it)
+                .getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE)
+        doReturn(resolver).`when`(it).contentResolver
+        doReturn(resources).`when`(it).resources
+        doReturn(it).`when`(it).createConfigurationContext(any())
+        Settings.Global.putString(resolver, NETWORK_AVOID_BAD_WIFI, "1")
+    }
+    private val tracker = MultinetworkPolicyTracker(context, null /* handler */)
+
+    private fun assertMultipathPreference(preference: Int) {
+        Settings.Global.putString(resolver, NETWORK_METERED_MULTIPATH_PREFERENCE,
+                preference.toString())
+        tracker.updateMeteredMultipathPreference()
+        assertEquals(preference, tracker.meteredMultipathPreference)
+    }
+
+    @Test
+    fun testUpdateMeteredMultipathPreference() {
+        assertMultipathPreference(MULTIPATH_PREFERENCE_HANDOVER)
+        assertMultipathPreference(MULTIPATH_PREFERENCE_RELIABILITY)
+        assertMultipathPreference(MULTIPATH_PREFERENCE_PERFORMANCE)
+    }
+
+    @Test
+    fun testUpdateAvoidBadWifi() {
+        Settings.Global.putString(resolver, NETWORK_AVOID_BAD_WIFI, "0")
+        assertTrue(tracker.updateAvoidBadWifi())
+        assertFalse(tracker.avoidBadWifi)
+
+        doReturn(1).`when`(resources).getInteger(R.integer.config_networkAvoidBadWifi)
+        assertTrue(tracker.updateAvoidBadWifi())
+        assertTrue(tracker.avoidBadWifi)
+    }
+
+    @Test
+    fun testOnActiveDataSubscriptionIdChanged() {
+        val testSubId = 1000
+        val subscriptionInfo = SubscriptionInfo(testSubId, ""/* iccId */, 1/* iccId */,
+                "TMO"/* displayName */, "TMO"/* carrierName */, 1/* nameSource */, 1/* iconTint */,
+                "123"/* number */, 1/* roaming */, null/* icon */, "310"/* mcc */, "210"/* mnc */,
+                ""/* countryIso */, false/* isEmbedded */, null/* nativeAccessRules */,
+                "1"/* cardString */)
+        doReturn(subscriptionInfo).`when`(subscriptionManager).getActiveSubscriptionInfo(testSubId)
+
+        // Modify avoidBadWifi and meteredMultipathPreference settings value and local variables in
+        // MultinetworkPolicyTracker should be also updated after subId changed.
+        Settings.Global.putString(resolver, NETWORK_AVOID_BAD_WIFI, "0")
+        Settings.Global.putString(resolver, NETWORK_METERED_MULTIPATH_PREFERENCE,
+                MULTIPATH_PREFERENCE_PERFORMANCE.toString())
+
+        val listenerCaptor = ArgumentCaptor.forClass(
+                ActiveDataSubscriptionIdChangedListener::class.java)
+        verify(telephonyManager, times(1))
+                .registerPhoneStateListener(any(), listenerCaptor.capture())
+        val listener = listenerCaptor.value
+        listener.onActiveDataSubscriptionIdChanged(testSubId)
+
+        // Check it get resource value with test sub id.
+        verify(subscriptionManager, times(1)).getActiveSubscriptionInfo(testSubId)
+        verify(context).createConfigurationContext(argThat { it.mcc == 310 && it.mnc == 210 })
+
+        // Check if avoidBadWifi and meteredMultipathPreference values have been updated.
+        assertFalse(tracker.avoidBadWifi)
+        assertEquals(MULTIPATH_PREFERENCE_PERFORMANCE, tracker.meteredMultipathPreference)
+    }
+}