Fixed NPE when trying to remove an item that does not exist. JM-392

git-svn-id: http://svn.igniterealtime.org/svn/repos/messenger/trunk@2798 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/messenger/roster/Roster.java

@@ -329,7 +329,9 @@ public class Roster implements Cacheable {
             throw new SharedGroupException("Cannot remove contact that belongs to a shared group");
         }
 
+        if (itemToRemove != null) {
             RosterItem.SubType subType = itemToRemove.getSubStatus();
+
             // Cancel any existing presence subscription between the user and the contact
             if (subType == RosterItem.SUB_TO || subType == RosterItem.SUB_BOTH) {
                 Presence presence = new Presence();
@@ -338,6 +340,7 @@ public class Roster implements Cacheable {
                 presence.setType(Presence.Type.unsubscribe);
                 server.getPacketRouter().route(presence);
             }
+
             // cancel any existing presence subscription between the contact and the user
             if (subType == RosterItem.SUB_FROM || subType == RosterItem.SUB_BOTH) {
                 Presence presence = new Presence();
@@ -346,8 +349,10 @@ public class Roster implements Cacheable {
                 presence.setType(Presence.Type.unsubscribed);
                 server.getPacketRouter().route(presence);
             }
+
             // If removing the user was successful, remove the user from the subscriber list:
             RosterItem item = rosterItems.remove(user.toBareJID());
+
             if (item != null) {
                 // Delete the item from the provider if the item is persistent. RosteItems that only
                 // belong to shared groups won't be persistent
@@ -362,8 +367,11 @@ public class Roster implements Cacheable {
                 roster.addItem(user, org.xmpp.packet.Roster.Subscription.remove);
                 broadcast(roster);
             }
+
             return item;
+        }
 
+        return null;
     }
 
     /**