SOLR-6631: DistributedQueue spinning on calling zookeeper getChildren()

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1635142 13f79535-47bb-0310-9956-ffa450edef68
Backout fix for SOLR-6631 as things like create collection are hanging now

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1635157 13f79535-47bb-0310-9956-ffa450edef68