Ticket 48944 - on a read only replica invalid state info can accumulate
Bug Description: if internal mods are generated on a consumer (eg by Account Policy)
and changes for these attributes are als received via replication
the state information on the consumer can accumulate
Fix Description: Make sure replace operations are only applied if they
are newer than an existing attribute deletion csn.
https://fedorahosted.org/389/ticket/48944
Reviewed by: Noriko, thanks