Specify explicitly FLAG_IMMUTABLE for PendingIntent

The existing pending intent in the BatteryTipUtils has been specified
FLAG_UPDATE_CURRENT. This change is to add explicitly FLAG_IMMUTABLE
to the pending intent.

Fixes: 171506726
Test: build pass, robotest
Change-Id: Ib82ddb45e05b492eef300f2ec064803d768419d0

src/com/android/settings/fuelgauge/batterytip/BatteryTipUtils.java

@@ -124,7 +124,7 @@ public class BatteryTipUtils {
             throws StatsManager.StatsUnavailableException {
         final Intent extraIntent = new Intent(context, AnomalyDetectionReceiver.class);
         final PendingIntent pendingIntent = PendingIntent.getBroadcast(context, REQUEST_CODE,
-                extraIntent, PendingIntent.FLAG_UPDATE_CURRENT);
+                extraIntent, PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_IMMUTABLE);
         statsManager.setBroadcastSubscriber(pendingIntent,
                 StatsManagerConfig.ANOMALY_CONFIG_KEY, StatsManagerConfig.SUBSCRIBER_ID);
     }