dispatch: fix silly blackbox entries when hg is interrupted When hg is interrupted, it creates ui.log like this: 1970/01/01 00:00:00 user @0000000000000000000000000000000000000000 (62488)> killed! exited 255 after 1.78 seconds This is due to a scoping problem: two different uses of the name "msg" collide. So rename one of them. Differential Revision: https://phab.mercurial-scm.org/D12427

tests: stop excluding the pycompat module from pyflakes I assume this was skipped because of all of the py2 stuff causing a lot of spew. The "unused" imports are left in place in case any 3rd party stuff is using it. I don't care about most of it, but TortoiseHg uses `io` and `queue`, so minimally I'd like to keep those. Differential Revision: https://phab.mercurial-scm.org/D12423

tests: drop some py2 specific pyflake failures Differential Revision: https://phab.mercurial-scm.org/D12422

util: drop a duplicate import This was already imported several lines above. Differential Revision: https://phab.mercurial-scm.org/D12421

pycompat: drop the pickle import I suspect this is what df56e6bd37f6 meant to eliminate. Differential Revision: https://phab.mercurial-scm.org/D12420

util: restore the util.pickle symbol This was accidently dropped in df56e6bd37f6, which started importing pickle directly. That commit explicitly says it will retain it for compatibility with external stuff though. The unused import in pycompat isn't flagged because that module is skipped. Just importing with a comment seemed cleaner than `import X as Y` and then assigning to a `pickle` variable, just to avoid the pyflakes warning. Differential Revision: https://phab.mercurial-scm.org/D12419