I'd like to take over this bug.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2536c3002ddfb7d229585dda40dc1fe427469aa2

commit 2536c3002ddfb7d229585dda40dc1fe427469aa2
Author: Gyuyoung Kim <gyuyoung@igalia.com>
Date: Tue Jan 15 14:50:24 2019

s13n: Eliminate signin_error_notifier_factory_ash.cc's include of profile_oauth2_token_service.h

There is no use of ProfileOAuth2TokenService in signin_error_notifier_factory_ash.cc.
We don't need to keep the include of profile_oauth2_token_service.h.

Bug:  921612 
Change-Id: Id8c857cc36e6e8c342f1ee559d91eb26f7d7d219
Reviewed-on: https://chromium-review.googlesource.com/c/1410833
Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Commit-Queue: Gyuyoung Kim <gyuyoung@igalia.com>
Cr-Commit-Position: refs/heads/master@{#622852}
[modify] https://crrev.com/2536c3002ddfb7d229585dda40dc1fe427469aa2/chrome/browser/signin/signin_error_notifier_factory_ash.cc