Enable Dark Mode by default on Mac

Bug: 850098
Change-Id: I454c77d5c47fcdc90ed7a4265cf4f268186a983b
Reviewed-on: https://chromium-review.googlesource.com/c/1431715
Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#625671}
1 file changed