evolve: store the old other divergent node after relocation in evolvestate
When the content-divergent changes are on different parents and we relocate of
the node to the parent of another one, we get a new other-divergent node. We
still need to store the older other-divergent in evolvestate so that we can use
that information.
#require test-repo
$ checkflake8() {
> if ! (which flake8 > /dev/null); then
> echo skipped: missing tool: flake8;
> exit 80;
> fi;
> };
$ checkflake8
Copied from Mercurial core (60ee2593a270)
$ cd "`dirname "$TESTDIR"`"
run flake8 if it exists; if it doesn't, then just skip
$ hg files -0 'set:(**.py or grep("^#!.*python")) - removed()' \
> -X hgext3rd/evolve/thirdparty \
> 2>/dev/null \
> | xargs -0 flake8