authpolicy: Add ActiveDirectoryUserStatus protobuf

Required for new GetUserStatus D-Bus call from Chrome to authpolicy
(see CL:481319).

BUG=chromium:710452
TEST=Emerges and works with dependent CL.

Change-Id: Ia6374a0ff2f9cd637447dd2b1b7ed007e297451d
Reviewed-on: https://chromium-review.googlesource.com/481299
Commit-Ready: Lutz Justen <ljusten@chromium.org>
Tested-by: Lutz Justen <ljusten@chromium.org>
Reviewed-by: Roman Sorokin <rsorokin@chromium.org>
4 files changed