Fix NPE for VVM Sync sms messages.

Return 0 for fields with null values in the VVM SyncMessage.

Bug: 23211613
Change-Id: I360abd14fec2dab5ffe2da0016d39d34a7b78323
diff --git a/src/com/android/phone/vvm/omtp/sms/SyncMessage.java b/src/com/android/phone/vvm/omtp/sms/SyncMessage.java
index 9a78a6d..6829981 100644
--- a/src/com/android/phone/vvm/omtp/sms/SyncMessage.java
+++ b/src/com/android/phone/vvm/omtp/sms/SyncMessage.java
@@ -71,7 +71,7 @@
      * @return the number of new messages stored on the voicemail server.
      */
     public int getNewMessageCount() {
-        return mNewMessageCount;
+        return mNewMessageCount != null ? mNewMessageCount : 0;
     }
 
     /**
@@ -101,7 +101,7 @@
      * {@link com.android.phone.vvm.omtp.OmtpConstants#NEW_MESSAGE}
      */
     public int getLength() {
-        return mMessageLength;
+        return mMessageLength != null ? mMessageLength : 0;
     }
 
     /**
@@ -121,6 +121,6 @@
      * {@link com.android.phone.vvm.omtp.OmtpConstants#NEW_MESSAGE}
      */
     public long getTimestampMillis() {
-        return mMsgTimeMillis;
+        return mMsgTimeMillis != null ? mMsgTimeMillis : 0;
     }
 }
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