GitLab

Why: we don't want floc to change more often than the intended
scheduled update cadence.

What:
- For each history-delete notification, if it's all-history or
the time-range overlaps with the time range of the history used to
compute the floc, we invalidate the floc. Otherwise, we keep using the
current floc.
- Remove the mechanism caching the swaa_nac_account_enabled status.
It's no longer needed as we don't need to query more often than the
scheduled update rate (% rare race condition).

How: Store history_begin_time_/history_end_time_ fields to FlocId.
Compare these fields with the history delete info.

Bug: 1143597
Change-Id: I685fd1a10cbc8044e799d7a644dfa2b7bb82ddd4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2507454
Commit-Queue: Yao Xiao <yaoxia@chromium.org>
Reviewed-by: Josh Karlin <jkarlin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826680}