SOLR-6024: Fix StatsComponent when using docValues=true multiValued=true (merge r1622525)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene_solr_4_10@1624097 13f79535-47bb-0310-9956-ffa450edef68
Merged revision(s) 1624073 from lucene/dev/branches/branch_4x:
LUCENE-5934: Fix backwards compatibility for 4.0 indexes.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene_solr_4_10@1624100 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5863: backport

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene_solr_4_10@1624103 13f79535-47bb-0310-9956-ffa450edef68