I thought we had an issue to do this but I can't find it so here is a new one.
Currently, in master branch, HMaster is a RegionServer and carries meta regions such as hbase:meta. Disable this facility by default until better thought through (I think we should undo master ever carrying regions; FBers are thinking we should go forward with notion that master carries meta/system regions. TODO). I want to disable it because this facility is not finished and meantime I want to test new stuff coming in on master branch w/o this new feature getting in the way.
Parking here a patch that has how to disable master carrying regions and a probably redundant test that ensures all works when master is not carrying meta regions (added because it WASN'T working for me – but was pilot error).