Implement source destination limit priority FIFO algorithm

This CL implements the logic in source registration processing in the
storage layer. The priority registration will be in a follow-up.

https://github.com/WICG/attribution-reporting-api/pull/1217

Note that we don't gate the trigger time change for fake event-level
reports from window end time to window start time, as currently the
trigger time is not used and there's no functionality change.

Bug: 347657122
Change-Id: Ic186d89146594b825facb8fb4172065c86687cff
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5540875


Reviewed-by: Andrew Paseltiner <apaseltiner@chromium.org>
Reviewed-by: Charlie Harrison <csharrison@chromium.org>
Reviewed-by: Joe Mason <joenotcharles@google.com>
Commit-Queue: Nan Lin <linnan@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1316542}