[0.94] Just OPENED regions are ignored by ServerShutdownHandler and go unassigned for ever

Visiting a user today, I came across following interesting case (0.94.2 HBase).

A server was added to cluster. It was assigned regions by the balancer. A bunch opened on the regionserver and just after the open, the regionserver was manually shutdown. There was a lag processing the zk region open events in the master (because clean shutdown, there was no zk activity when the regions were closed on the shutdown regionserver). Processing the server shutdown, we do this for a good few of the regions that had just been opened on the regionserver:

2013-01-30 02:41:19,917 INFO org.apache.hadoop.hbase.master.handler.ServerShutdownHandler: Skip assigning region OBFUSCATED_TABLE,OBFUSCATED_STARTROW,1344723216908.55e9cb551edeea0b52bb91af7c2de199. state=OPEN, ts=1359513674715, server=XX.XX.18.40,10304,1359513445136

Seems like outright bug that'd we'd skip a region that is in transition that is in the OPEN state.

More detail to follow.