evolve: in pubdiv resolution make sure that transaction get closed
Before this patch it could be possible that transaction won't get
closed if res is False in the pubic divergence resolution when
continuing the hg evolve.
#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 -I 'set:(**.py or grep("^#!.*python")) - removed()' 2>/dev/null \
> | xargs pyflakes 2>/dev/null