SOLR-4952: ConvertedLegacyTest shouldn't assuming an absolute score now that we are randomizing merge policy settings, term stats may fluctuate

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1511044 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5107: Fixed NPE when using numTerms=0 in LukeRequestHandler

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1511064 13f79535-47bb-0310-9956-ffa450edef68