GitLab

r584330 updated all annotations on ObserverList declarations to be
::Unchecked, but a few new declarations appeared since that. They
need to be ::Unchecked as well in order for https://crrev.com/c/1053338
to land cleanly.

TBR=gab@chromium.org

Bug: 842987
Cq-Include-Trybots: luci.chromium.try:linux_mojo
Change-Id: I1c6d7ae8e9668438afa8184fd0c3884a21e9732d
Reviewed-on: https://chromium-review.googlesource.com/1182712
Commit-Queue: Trent Apted <tapted@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584682}