Fixing JSCBC-25 test (previously would never fail)

Change-Id: I0f1748bf0b41c8f129629e04c88ce99d89d64008
Reviewed-on: http://review.couchbase.org/28997
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Brett Lawson <brett19@gmail.com>