SOLR-6161: SolrDispatchFilter should throw java.lang.Error back even if wrapped in another exception

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1602591 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6153: ReplicationHandler backup response format should contain backup name

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1602593 13f79535-47bb-0310-9956-ffa450edef68