[permissions] Add background-sync permission. (#61)

Please take a look. This is related to #60.
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/permissions/pull/61

-- Commit Summary --

  * Add background-sync permission.

-- File Changes --

    M index.html (13)

-- Patch Links --

https://github.com/w3c/permissions/pull/61.patch
https://github.com/w3c/permissions/pull/61.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/permissions/pull/61