SOLR-5986: Removing a todo that was introduced with a prior commit. It doesn't make any sense now as partialResults are now returned in all cases where timeAllowed kicks in (merge from trunk)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1631146 13f79535-47bb-0310-9956-ffa450edef68