GitLab

 - Media query only
 - Force dark unless page supports dark mode via meta tag and media query
 - Always force dark (disable media query).

Bug: 1001516
Change-Id: Ida620311e8b4811f6fddffbeaf9d7f40b427493e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1798349Reviewed-by: Tobias Sargeant <tobiasjs@chromium.org>
Commit-Queue: Anna Malova <amalova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695633}