SOLR-5709: Highlighting grouped duplicate docs from different shards with group.limit > 1 throws ArrayIndexOutOfBoundsException

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1566743 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5536: Added a proper ValueSource context

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1566754 13f79535-47bb-0310-9956-ffa450edef68