Standalone clients don't have communicators.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@5129 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/presents/client/Client.java

@@ -561,8 +561,10 @@ public class Client
         _connectionId = data.connectionId;
         _cloid = data.clientOid;
 
-        // notify the communicator that we got our bootstrap data
-        _comm.gotBootstrap();
+        // notify the communicator that we got our bootstrap data (if we have one)
+        if (_comm != null) {
+            _comm.gotBootstrap();
+        }
 
         // initialize our invocation director
         _invdir.init(omgr, _cloid, this);