RowMutationType.UPDATE_ROW with non-existant rowId

[Tom Hood]

Hi,

I'm using blur 0.2.4 and I expected to get a BlurException from
Iface.mutate when mutating a row whose rowId does not exist.  The type of
mutation was:

RowMutationType = UPDATE_ROW
RecordMutationType = REPLACE_ENTIRE_RECORD

Instead of an exception, the row was added.  Is the code working as
intended and the RowMutationType.UPDATE_ROW javadoc is out of date or is it
a bug?

Thanks,
-- Tom