It turns out, we don't need to `mk_add_options export` the variables
from the in-tree mozconfigs. If anything, that causes problems when
trying to simplify the mozconfigs, because it makes the variables
exported from .mozconfig.mk, overriding what configure may change and
store in autoconf.mk.
All the variables are handled by configure in a way that makes them
available in autoconf.mk, so there's no loss there, and with the
python/shell-based mozconfig loader, it turns out we don't need to go
through extra normalization via cmd.
autospider.py, being its own pseudo-mozconfig parser, still does need
it, though, but it was hooking into it already, so just inline that.
Differential Revision: https://phabricator.services.mozilla.com/D17769
--HG--
extra : moz-landing-system : lando
The `cd $PATH && pwd` pattern doesn't work when $PATH doesn't exist, so
move them in a block only executed when the directory exists.
--HG--
extra : rebase_source : 53bd2959dbd9825526a386b6ab5b40a7f67a5d20