Fix VCN crash when retrieving carrier config while phone is gone

This CL calls CarrierConfigManager.getCarrierConfigSubset instead of
getConfigForSubId to guard against crashing when phone process has gone.

The former method is designed for system components to retrieve carrier
configs with consideration of phone process may be gone (e.g. during
rebooting from previous crash).

Bug: 319791612
Test: atest TelephonySubscriptionTrackerTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:d7ebd7c10712a8a319ae6117949d4ece92be4de8)
Merged-In: I784610b243db2a666c1fe89b1438950a2f6a1478
Change-Id: I784610b243db2a666c1fe89b1438950a2f6a1478

2 files changed, 20 insertions, 0 deletions

diff --git a/tests/vcn/Android.bp b/tests/vcn/Android.bp
index bc1df75bb142..ee2e7cfcd480 100644
--- a/tests/vcn/Android.bp
+++ b/tests/vcn/Android.bp
@@ -31,6 +31,7 @@ android_test {
         "platform-test-annotations",
         "services.core",
         "service-connectivity-tiramisu-pre-jarjar",
+        "flag-junit",
     ],
     libs: [
         "android.test.runner",
diff --git a/tests/vcn/java/com/android/server/vcn/TelephonySubscriptionTrackerTest.java b/tests/vcn/java/com/android/server/vcn/TelephonySubscriptionTrackerTest.java
index 34f884b94296..887630b03a8c 100644
--- a/tests/vcn/java/com/android/server/vcn/TelephonySubscriptionTrackerTest.java
+++ b/tests/vcn/java/com/android/server/vcn/TelephonySubscriptionTrackerTest.java
@@ -38,6 +38,7 @@ import static org.mockito.ArgumentMatchers.argThat;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.atLeastOnce;
 import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.times;
@@ -58,6 +59,7 @@ import android.os.HandlerExecutor;
 import android.os.ParcelUuid;
 import android.os.PersistableBundle;
 import android.os.test.TestLooper;
+import android.platform.test.flag.junit.SetFlagsRule;
 import android.telephony.CarrierConfigManager;
 import android.telephony.SubscriptionInfo;
 import android.telephony.SubscriptionManager;
@@ -71,7 +73,10 @@ import android.util.ArraySet;
 import androidx.test.filters.SmallTest;
 import androidx.test.runner.AndroidJUnit4;
 
+import com.android.internal.telephony.flags.Flags;
+
 import org.junit.Before;
+import org.junit.Rule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
@@ -128,6 +133,9 @@ public class TelephonySubscriptionTrackerTest {
         TEST_SUBID_TO_CARRIER_CONFIG_MAP = Collections.unmodifiableMap(subIdToCarrierConfigMap);
     }
 
+    @Rule public final SetFlagsRule mSetFlagsRule = new SetFlagsRule();
+
+
     @NonNull private final Context mContext;
     @NonNull private final TestLooper mTestLooper;
     @NonNull private final Handler mHandler;
@@ -185,6 +193,7 @@ public class TelephonySubscriptionTrackerTest {
 
     @Before
     public void setUp() throws Exception {
+        mSetFlagsRule.enableFlags(Flags.FLAG_FIX_CRASH_ON_GETTING_CONFIG_WHEN_PHONE_IS_GONE);
         doReturn(2).when(mTelephonyManager).getActiveModemCount();
 
         mCallback = mock(TelephonySubscriptionTrackerCallback.class);
@@ -594,4 +603,14 @@ public class TelephonySubscriptionTrackerTest {
                 new ArraySet<>(Arrays.asList(TEST_SUBSCRIPTION_ID_1, TEST_SUBSCRIPTION_ID_2)),
                 snapshot.getAllSubIdsInGroup(TEST_PARCEL_UUID));
     }
+
+    @Test
+    public void testCarrierConfigChangeWhenPhoneIsGoneShouldNotCrash() throws Exception {
+        doThrow(new IllegalStateException("Carrier config loader is not available."))
+                .when(mCarrierConfigManager)
+                .getConfigForSubId(eq(TEST_SUBSCRIPTION_ID_1), any());
+
+        sendCarrierConfigChange(true /* hasValidSubscription */);
+        mTestLooper.dispatchAll();
+    }
 }