OF-616: Public Group cache should be refreshed after a group is deleted.

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/trunk@13491 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/openfire/group/GroupManager.java

@@ -117,7 +117,8 @@ public class GroupManager {
                 groupMetaCache.remove(GROUP_COUNT_KEY);
                 groupMetaCache.remove(GROUP_NAMES_KEY);
                 groupMetaCache.remove(SHARED_GROUPS_KEY);
-                
+                groupMetaCache.remove(PUBLIC_GROUPS);
+
                 // Evict cached information for affected users
                 evictCachedUsersForGroup(group);
             }