fix test bug

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1539721 13f79535-47bb-0310-9956-ffa450edef68
fix typo in comment

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1539768 13f79535-47bb-0310-9956-ffa450edef68