Also please add "User don't have the right to join the domain" error.

Also we need to investigate if machine_name could be bad for some reason.

Also we should handle "Our netbios name can be at most 15 chars long"

User joined too many machines:
Failed to join domain: failed to join domain 'CHROME.LAN' over rpc: Insufficient quota exists to complete the operation.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform/system_api/+/eb397c32a942a2839b2aa3638b6c0da5c3bee146

commit eb397c32a942a2839b2aa3638b6c0da5c3bee146
Author: Roman Sorokin <rsorokin@chromium.org>
Date: Thu Jan 12 17:57:30 2017

authpolicy: Add new errors

Also added explicit numbers to the enum values.

BUG= chromium:680095 
TEST=manual

Change-Id: I7d23286b1f9d83f2dcca562dc857a959e597a6c0
Reviewed-on: https://chromium-review.googlesource.com/427839
Commit-Ready: Lutz Justen <ljusten@chromium.org>
Tested-by: Roman Sorokin <rsorokin@chromium.org>
Reviewed-by: Lutz Justen <ljusten@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>

[modify] https://crrev.com/eb397c32a942a2839b2aa3638b6c0da5c3bee146/dbus/authpolicy/dbus-constants.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/9c6fdf943b8c5b3535a2279e457c5dc20b6257c4

commit 9c6fdf943b8c5b3535a2279e457c5dc20b6257c4
Author: Roman Sorokin <rsorokin@chromium.org>
Date: Thu Jan 12 18:00:53 2017

authpolicy: Handle more errors

Network, bad machine name, user denied to join the domain, quota on
joined machines etc.

BUG= chromium:680095 
TEST=manual

Change-Id: Ia7dffb81fee88c49178a71c8f4428452f45ab07f
Reviewed-on: https://chromium-review.googlesource.com/427819
Commit-Ready: Roman Sorokin <rsorokin@chromium.org>
Tested-by: Roman Sorokin <rsorokin@chromium.org>
Reviewed-by: Thiemo Nagel <tnagel@chromium.org>

[modify] https://crrev.com/9c6fdf943b8c5b3535a2279e457c5dc20b6257c4/authpolicy/samba_interface.cc

bulk Verify of older or not-user-facing Chromad bugs