Publish default/fallback CarrierService package.

Bug: 63391323
Test: bit FrameworksCoreTests:android.util.RecurrenceRuleTest
Test: bit FrameworksServicesTests:com.android.server.NetworkPolicyManagerServiceTest
Exempt-From-Owner-Approval: Bug 63673347
Change-Id: I93fae4a43e58e9e4c32f8bf345a257dcd607f088
diff --git a/src/com/android/phone/CarrierConfigLoader.java b/src/com/android/phone/CarrierConfigLoader.java
index a33324b..b137e5f 100644
--- a/src/com/android/phone/CarrierConfigLoader.java
+++ b/src/com/android/phone/CarrierConfigLoader.java
@@ -715,6 +715,11 @@
     }
 
     @Override
+    public String getDefaultCarrierServicePackageName() {
+        return mPlatformCarrierConfigPackage;
+    }
+
+    @Override
     public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
         if (mContext.checkCallingOrSelfPermission(android.Manifest.permission.DUMP)
                 != PackageManager.PERMISSION_GRANTED) {