Merged revision(s) 1586301 from lucene/dev/trunk:
Fix test that fails on Windows if it gets a FSDirectory (it intentionally does not close IW/IR). The new cleanup code then complains about inability to delete the index dir

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1586303 13f79535-47bb-0310-9956-ffa450edef68