bug#63845: unbound evaluate-populate-directive variable error with guix shell -C --symlink

[Maxim Cournoyer <maxim.cournoyer@gmail.com>]

Hi,

This appears to be a recent regression:

--8<---------------cut here---------------start------------->8---
$ LANG=C guix shell --container --symlink=/usr/bin/env=bin/env coreutils 
;;; Failed to autoload evaluate-populate-directive in (gnu build install):
;;; no code for module (gnu build install)
Backtrace:
          18 (primitive-load "/home/maxim/.config/guix/current/bin/g?")
In guix/ui.scm:
   2300:7 17 (run-guix . _)
  2263:10 16 (run-guix-command _ . _)
In ice-9/boot-9.scm:
  1752:10 15 (with-exception-handler _ _ #:unwind? _ # _)
  1752:10 14 (with-exception-handler _ _ #:unwind? _ # _)
In guix/store.scm:
   659:37 13 (thunk)
   1298:8 12 (call-with-build-handler _ _)
   1298:8 11 (call-with-build-handler #<procedure 7f2709325510 at g?> ?)
In guix/status.scm:
    839:4 10 (call-with-status-report _ _)
In guix/scripts/environment.scm:
  1152:11  9 (_)
In guix/store.scm:
  2168:25  8 (run-with-store #<store-connection 256.99 7f270924b4b0> ?)
In guix/scripts/environment.scm:
    864:8  7 (_ _)
In gnu/build/linux-container.scm:
   397:16  6 (call-with-container (#<<file-system> device: "none?> ?) ?)
   265:16  5 (run-container _ _ (cgroup mnt pid ipc uts user net) _ # ?)
In guix/scripts/environment.scm:
   894:14  4 (_)
In srfi/srfi-1.scm:
    634:9  3 (for-each #<procedure 7f271a45bc90 at guix/scripts/env?> ?)
In guix/scripts/environment.scm:
   894:29  2 (_ (directory "/usr/bin"))
In ice-9/boot-9.scm:
  1685:16  1 (raise-exception _ #:continuable? _)
  1685:16  0 (raise-exception _ #:continuable? _)

ice-9/boot-9.scm:1685:16: In procedure raise-exception:
error: evaluate-populate-directive: unbound variable
--8<---------------cut here---------------end--------------->8---

Tested with commit 99fc7e5dd3c9c92f9b6c2e51db9dc5b0481a56b2.

-- 
Thanks,
Maxim