For small-ish realms (<= 250 users), we ensure that the presence
info includes all realm users the front end knows about, even in
cases where the server sends down a slimmed version of presence
data. We make the users "offline" by default, of course.
This commit sets us up to optimize larger realms without concerns
of breaking small realms. Small realms may want to continue to
show all users, even users who may have been offline several weeks,
since it doesn't clutter their API as much as it would for big
realms.
Most of this code was simply moved from activity.js with some
minor renaming of functions like set_presence_info -> set_info.
Some functions were slightly nontrivial extractions:
is_not_offline:
came from activity.huddle_fraction_present
get_status/get_mobile:
simple getters
set_user_status:
partial extraction from activity.set_user_status
last_active_date:
pulled out of admin.js code
We also fixed activity.filter_and_sort to take user_ids.
Steve Howell