e994d033a6
RingBuilder._reassign_parts() is really moving one (partition, replica) pair at a time. However, the way that _gather_reassign_parts passes that data in was strange; it would update each replica's entry in _replica2part2dev to 0xffff, then return a list of affected partitions. Now it just returns the pairs to move. This is helpful in the presence of bugs that affect partition assignment (e.g. #943493), there's no chance of stray 0xffff values hanging around and corrupting the partition map. Also, update my email address. Change-Id: Ifb3aeb4fac750f66e2ddbad88eb5846e72bac20c