DEP8 tests using the built package source

[Jakub Wilk]

* Stephen Kitt <skitt at debian.org>, 2014-03-19, 23:25:
>>FTR, we explicitly make use of that for our toolchain packages: gcc, 
>>binutils, linux, and eglibc have a "bin/true" test with "needs build" 
>>to ensure that whenever we update one piece, the others are still 
>>buildable and their tests succeed (which run at build time). I know 
>>that this is somewhat of an abuse of autopkgtest, but it does work :-)
>
>So effectively it becomes a "rebuild reverse-dependencies" tool as 
>well, nice!

If we had enough hardware to throw at the problem, I'd love to see 
ci.debian.net rebuilding all packages, even those without any DEP-8 
tests defined. Hopefully there's a better way to achieve that than 
patching 20 thousands of source packages. :)

-- 
Jakub Wilk