Sprint: MMS cannot be sent in the UK

     This is due to Sprint network at UK is actually GSM/UMTS. Thus we need GSM phone with CSIM to provide Nai too.

Bug:18241756
Change-Id: Icec10c88834151f5e35e38db93af36d7f40890fd
diff --git a/telephony/java/android/telephony/TelephonyManager.java b/telephony/java/android/telephony/TelephonyManager.java
index fe717dd..8d438e3 100644
--- a/telephony/java/android/telephony/TelephonyManager.java
+++ b/telephony/java/android/telephony/TelephonyManager.java
@@ -703,7 +703,11 @@
     public String getNai(int slotId) {
         int[] subId = SubscriptionManager.getSubId(slotId);
         try {
-            return getSubscriberInfo().getNaiForSubscriber(subId[0]);
+            String nai = getSubscriberInfo().getNaiForSubscriber(subId[0]);
+            if (Log.isLoggable(TAG, Log.VERBOSE)) {
+                Rlog.v(TAG, "Nai = " + nai);
+            }
+            return nai;
         } catch (RemoteException ex) {
             return null;
         } catch (NullPointerException ex) {