Check for null data before writing contact rows to server

Change-Id: Ib7016c43b2655e1753680c511f30cad8f4a1acce
diff --git a/src/com/android/exchange/adapter/ContactsSyncAdapter.java b/src/com/android/exchange/adapter/ContactsSyncAdapter.java
index c5bf74e..1fb885e 100644
--- a/src/com/android/exchange/adapter/ContactsSyncAdapter.java
+++ b/src/com/android/exchange/adapter/ContactsSyncAdapter.java
@@ -1556,6 +1556,7 @@
 
     private void sendPhone(Serializer s, ContentValues cv) throws IOException {
         String value = cv.getAsString(Phone.NUMBER);
+        if (value == null) return;
         switch (cv.getAsInteger(Phone.TYPE)) {
             case TYPE_WORK2:
                 s.data(Tags.CONTACTS_BUSINESS2_TELEPHONE_NUMBER, value);
@@ -1600,6 +1601,7 @@
 
     private void sendRelation(Serializer s, ContentValues cv) throws IOException {
         String value = cv.getAsString(Relation.DATA);
+        if (value == null) return;
         switch (cv.getAsInteger(Relation.TYPE)) {
             case Relation.TYPE_ASSISTANT:
                 s.data(Tags.CONTACTS_ASSISTANT_NAME, value);