[MERGE][1.2?][Bug #137823] Don't blindly raise UnavailableFeature during test setup

[John Arbash Meinel]

Vincent Ladeuil wrote:
> Hi,
> 
> This bug was nasty, see details on https://bugs.edge.launchpad.net/bzr/+bug/137823
> 
> The risk of broking anything is sufficiently low that this may be
> included in 1.2 if time permits.
> 
> Also note that this was caused by an unusual way to check the
> availability of the feature, it needed to be done in
> transport.ftp.get_test_permutations() with no access to the test
> itself (hence no access to neither _test_needs_features nor
> requireFeature()).
> 
>         Vincent

Why not change it so that raising an exception during setUp still calls tearDown?

John
=:->