Merge branch 'js/am-call-theirs-theirs-in-fallback-3way' into maint

One part of "git am" had an oddball helper function that called stuff from outside "his" as opposed to calling what we have "ours", which was not gender-neutral and also inconsistent with the rest of the system where outside stuff is usuall called "theirs" in contrast to "ours". * js/am-call-theirs-theirs-in-fallback-3way: am: counteract gender bias