GitLab

Introduces a new component for BackgroundSync so code can be shared with
WebLayer. Migrates BackgroundSyncPermissionContext and its unittest.

Bug: 1087486
Change-Id: Ib2968305dfa674eec81985f4ae19780ca5d6d9e3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2421491Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Reviewed-by: Josh Karlin <jkarlin@chromium.org>
Commit-Queue: Mugdha Lakhani <nator@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809874}