GitLab

"background-fetch" permission was added to the Permissions API with this
commit:
https://github.com/w3c/permissions/pull/183/commits/096436eb59caaa5b244b0514d84f287392cb069b

Chrome uses Automatic Downloads for this permission, so as not to add yet
another user facing permission to the UI. This CL:
1. Adds a background_fetch content setting, because that's needed
   by PermissionContext and allows us to decouple from Automatic
   Downloads content setting.
2. Adds a BackgroundFetch PermissionContext mapped to this content
   setting.
3. Makes this PermissionContext decide whether background fetch() is
   permitted, which we do by:
   a. Querying DownloadRequestLimiter when there' a top level frame.
   b. Querying the Automatic Downloads content setting in other cases.

For context and details, please see this document:
https://docs.google.com/document/d/1rPYSlbzScw_6PLUJ3m96ZLIkxXVAWyBSL75-VDJEMso/edit?usp=sharing

Bug: 886896
Change-Id: Id0fcc64d4242290f3782c61ef11babe5717b409f
Reviewed-on: https://chromium-review.googlesource.com/c/1233714
Commit-Queue: Mugdha Lakhani <nator@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: Rayan Kanso <rayankans@chromium.org>
Reviewed-by: Tobias Sargeant <tobiasjs@chromium.org>
Reviewed-by: Raymes Khoury <raymes@chromium.org>
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#597209}