Though maybe the remainder of it was removed afterward? Looks like

jar_map_*

is only used one place now:

~/Src/Pants master * find src -name '*.py' | xargs grep 'jar_map_'
src/python/pants/backend/jvm/tasks/ivy_resolve.py:      if self.context.products.isrequired('jar_map_{conf}'.format(conf=conf)):