GitLab

This change allows to save and retrieve an optional expiration time
property in the PushMessagingAppIdentifier and specifically in the
profile preferences.

It is saved in the same preference map as the (origin, SWR id) and will
be converted in a string as seconds from Windows epoch.

BUG: 1104215
Change-Id: I37d7f7cbc7d4160c049d72935b7d6d9bb308170e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2315682
Commit-Queue: Viviane Yang <viviy@google.com>
Reviewed-by: Rayan Kanso <rayankans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#791731}