LUCENE-4853: fix sort order bug with returned snippets

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1458949 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-4853: fix param name

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1458951 13f79535-47bb-0310-9956-ffa450edef68