Walk the whole index regardless of age.
Feed IDs the sync brought in or found changed: after a full walk, the reconciliation targets (new, changed, or active feeds); after a delta, the newly seen feeds. Empty when nothing moved or the roster was left alone.
Brings the feed roster up to date on a
/proc/jobsvisit. While the roster is younger than ROSTER_FULL_WALK_MS this is a delta: feeds whose id exceeds the highest known one, from both the owned/shared and the public collections (one call each when nothing is new). Once older, it is the full index walk, which is the only way a feed shared later, or one deleted, is seen. A roster still owned by warmup (not yetcurrent) is left alone.