GitLab

The initial commit was in 42f9c67b. The difference is:
- Left out testing/buildbot/chromium.win.json since it caused
  http://crbug.com/441690 and more investigation is needed.

TBR=jochen@chromium.org
R=jam@chromium.org
BUG=98637

Review URL: https://codereview.chromium.org/797483004

Cr-Commit-Position: refs/heads/master@{#308167}