[MERGE][bug #125784] Don't suppress original errors when .unlock() fails

[Martin Pool]

>> It is quite a bit more effort to multiply rather than subclass. Because the
>> multiplier is designed for adapting all tests in a module, so adapting just 1
>> class XX is kind of hard. 'load_tests' would let you do it, but you have to
>> 'iter_suite_tests(basic_tests)' and then figure out which ones need to be adapted.
>>
>> Or have them in a separate module, and adapt everything, etc.
>>
>> I'm not saying I wouldn't do it if pushed, just that in this case it would be a
>> lot more effort.
>
> I've had the same experience, although I admit I haven't checked with the most
> recent version of the multiplication code.  I would love for it to be as easy as
> subclassing.

OK, so let's hold it over.

-- 
Martin <http://launchpad.net/~mbp/>