We have the necessary infrastructure now via IdentityTestEnvironmentProfileAdaptor.

OK working on this then...

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/09c92d7a6b08216c43dc991001d8837a4e38b720

commit 09c92d7a6b08216c43dc991001d8837a4e38b720
Author: Sergio Villar Senin <svillar@igalia.com>
Date: Tue Nov 20 09:19:00 2018

Convert arc_session_manager_browsertest.cc to use IdentityManager

It was using both SigninManager and ProfileOAuth2TokenService fake
objects injected in the profile to signin the user with a refresh
token. The IdentityTestEnvironmentProfileAdaptor could be used to
create the testing profile followed by
IdentityTestEnvironment::MakePrimaryAccountAvailable() to perform the
signin.

Bug:  882864 
Change-Id: I6d546a722a0eda4f3d14d6234d819a3964c7d92e
Reviewed-on: https://chromium-review.googlesource.com/c/1338107
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: Elijah Taylor <elijahtaylor@chromium.org>
Commit-Queue: Sergio Villar <svillar@igalia.com>
Cr-Commit-Position: refs/heads/master@{#609637}
[modify] https://crrev.com/09c92d7a6b08216c43dc991001d8837a4e38b720/chrome/browser/chromeos/arc/arc_session_manager_browsertest.cc

Closing