Make getPackagesWithCarrierPrivilgesForAllPhones System API

Test: build
Bug: 145550382
Change-Id: Ie3ca4ba8e16938e769b75f2f1cac2737145e47a6
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index 8e88c7b..9d6cc83 100755
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -5293,9 +5293,17 @@
 
     @Override
     public List<String> getPackagesWithCarrierPrivilegesForAllPhones() {
+        enforceReadPrivilegedPermission("getPackagesWithCarrierPrivilegesForAllPhones");
+
+        final long identity = Binder.clearCallingIdentity();
+
         List<String> privilegedPackages = new ArrayList<>();
-        for (int i = 0; i < TelephonyManager.getDefault().getPhoneCount(); i++) {
-           privilegedPackages.addAll(getPackagesWithCarrierPrivileges(i));
+        try {
+            for (int i = 0; i < TelephonyManager.getDefault().getPhoneCount(); i++) {
+                privilegedPackages.addAll(getPackagesWithCarrierPrivileges(i));
+            }
+        } finally {
+            Binder.restoreCallingIdentity(identity);
         }
         return privilegedPackages;
     }