eclass-overlay: add modem-updater user

This user/group will be the one modemfwd runs under so it can be
sandboxed along with its tools.

BUG=b:37953355
TEST=emerge, display_accts.py

Change-Id: I20472df4249cfd9428ffe1479e37971be4cb7df0
Reviewed-on: https://chromium-review.googlesource.com/761837
Commit-Ready: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Eric Caruso <ejcaruso@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
2 files changed
tree: f38bfc525fb2f059e8e9d4d3b47a0dbfa7106154
  1. eclass/
  2. metadata/
  3. profiles/
  4. PRESUBMIT.cfg