GitLab

Migrates everything in base/task but post_job.h and lazy_task_runner.h
which will be migrated in their own CLs.

Bug: 1026641
Change-Id: If58acf8dd79ef848a16df210d4a283db10231a98
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1996991
Commit-Queue: Gabriel Charette <gab@chromium.org>
Reviewed-by: Etienne Pierre-Doray <etiennep@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735733}