evolve: delete evolvestate after aborting interrupted `next --evolve`
We didn't use to delete the evolvestate after aborting an interrupted `next
--evolve`. This patch makes sure we do that. The test changes demonstrate the
fix and we add a CHANGELOG entry about the fix.
#require test-repo pyflakes
Copied from Mercurial core (60ee2593a270)
$ cd "`dirname "$TESTDIR"`"
run pyflakes on all tracked files ending in .py or without a file ending
(skipping binary file random-seed)
$ hg locate 'set:(**.py or grep("^#!.*python")) - removed()' 2>/dev/null \
> | xargs pyflakes 2>/dev/null