HIVE-16686, we switched ReplCopyTask to always use a privileged DistCp. This, however, is incorrect for copying _metadata generated from a temporary scratch directory to hdfs. We need to change that so that routes to using a regular CopyTask. The issue with using distcp for this is that distcp launches from another job which may be queued on another machine, which does not have access to this file:// uri. Distcp should only ever be used when copying from non-localfilesystems.
Also, in the spirit of following up
HIVE-16686, we missed adding "-pb" as a default for invocations of distcp from hive. Adding that in. This would not be necessary if HADOOP-8143 had made it in, but till it doesn't go in, we need it.