GitLab

The accounts submenu positioning has to be
adjusted because native combobox menus on
Mac are always TOPLEFT aligned.

Screenshots:
https://drive.google.com/file/d/1yibhKX3giSaMrXaDXfEyQM99MAwIg2RF/view?usp=sharing
https://drive.google.com/file/d/14k2wIXyL37IPSQm0jNt9zj9ePZXBXZB-/view?usp=sharing

Bug: 813805
Change-Id: I04c60167f0123a320c10e579b77e834bc63a0b6f
Reviewed-on: https://chromium-review.googlesource.com/959321
Commit-Queue: Thomas Tangl <tangltom@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542783}