Let me take over this bug.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8a071bfbe7b4923d7ba5bec19ff1f6cbbab78300

commit 8a071bfbe7b4923d7ba5bec19ff1f6cbbab78300
Author: Gyuyoung Kim <gyuyoung@igalia.com>
Date: Mon Jan 21 08:55:03 2019

s13n: Remove stale device_oauth2_token_service-related includes from enrollment_handler_chromeos.cc

Clean up device_oauth2_token_service-related includes in enrollment_handler_chromeos.cc
There are no uses of DeviceOAuth2TokenService in enrollement_handler_chromeos.cc. This CL
removes the includes related to device_oauth2_token_service.h and factory.h.

Bug:  921601 
Change-Id: I5942e333a55083db1cf558fc0acd2f25d31bef78
Reviewed-on: https://chromium-review.googlesource.com/c/1414732
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Pavol Marko <pmarko@chromium.org>
Commit-Queue: Gyuyoung Kim <gyuyoung@igalia.com>
Cr-Commit-Position: refs/heads/master@{#624535}
[modify] https://crrev.com/8a071bfbe7b4923d7ba5bec19ff1f6cbbab78300/chrome/browser/chromeos/policy/enrollment_handler_chromeos.cc