fix for failing tests with gmime 2.6.19

[David Bremner]

Daniel Kahn Gillmor <dkg at fifthhorseman.net> writes:

>
> Please don't introduce this cruft into the notmuch codebase.  It should
> be fixed in gmime, not worked-around notmuch.
>
> I've just uploaded gmime 2.6.19-2 to unstable to address this issue.
>

Hi Daniel;

Thanks a lot for that. 

What I (still) wonder about is all the people not running Debian, in the
interval between the release of notmuch 0.17 and the next upstream
release of gmime (and propagation to various distros).  Even on Debian,
building on testing and backports complicates things a bit.

d