stablerange: fix merge slicing when range has multiple roots
The first element in the bottom set is not necessarly the one with the lowest
revision. We now properly compute and use the minimum value.
#require test-repo
$ checkcm() {
> if ! (which check-manifest > /dev/null); then
> echo skipped: missing tool: check-manifest;
> exit 80;
> fi;
> };
$ checkcm
$ cat << EOF >> $HGRCPATH
> [experimental]
> evolution=all
> EOF
Run check manifest:
$ cd $TESTDIR/..
$ check-manifest
lists of files in version control and sdist match