When implement the procedure of replication admin operations, we abstract a replication storage interface in
HBASE-19543. So ReplicationQueues/ReplicationQueuesClient are not used anymore. These interface are IA.private. So it is ok to remove them. But there are two config: hbase.region.replica.replication.replicationQueues.class and hbase.region.replica.replication.replicationQueuesClient.class in ReplicationFactory. These configs were introduced by HBASE-15867, which only in 2.0. And the feature development is not active now. In the future, we can implement the table based replication to replication storage interface. So let's remove them before release 2.0.
See more details in the discussion of