Use FLAG_IMMUTABLE

Require that the PendingIntent be immutable so that a malicious app is
 not able to hijack and mutate any of the details.

Test: Android builds
Bug: 155094269
Change-Id: If127b73c975b5b3f004500de7f9baa6a7bc00ce4
Merged-In: If127b73c975b5b3f004500de7f9baa6a7bc00ce4
(cherry picked from commit a2183fe79011ec08812f883b90e4a6604c184ccf)
diff --git a/src/java/com/android/internal/telephony/ServiceStateTracker.java b/src/java/com/android/internal/telephony/ServiceStateTracker.java
index db566ef..8dabcb5 100644
--- a/src/java/com/android/internal/telephony/ServiceStateTracker.java
+++ b/src/java/com/android/internal/telephony/ServiceStateTracker.java
@@ -2498,7 +2498,8 @@
                     AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
 
                     Intent intent = new Intent(ACTION_RADIO_OFF);
-                    mRadioOffIntent = PendingIntent.getBroadcast(context, 0, intent, 0);
+                    mRadioOffIntent = PendingIntent.getBroadcast(
+                            context, 0, intent, PendingIntent.FLAG_IMMUTABLE);
 
                     mAlarmSwitch = true;
                     if (DBG) log("Alarm setting");