SOLR-6453

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1627343 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6511: Fencepost error in LeaderInitiatedRecoveryThread; refactor HttpPartitionTest to resolve jenkins failures.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1627347 13f79535-47bb-0310-9956-ffa450edef68