Allow filtering by $parent when asking for highest modification sequence.
Never used.
Merge branch 'master' into history
Need to get the size in this case as well.
Existence check
Merge branch 'master' into history
Delegate fetching of SyncStamp (either timestamp or modseq) to driver.
Add migration file for history modification sequences.
Add support for ActiveSync using history modification sequences in Core.
Add support for history modification sequences to groupware apps.
CHANGES
Fix @since tags.
CHANGES
Fix copy/paste error.
Use the interface name.
Prevent race condition when there is no history data.

If there is no existing history data, we will have an empty sequence,
which will trigger the initial sync. Catch this by remembering that
we have initially syncronized the collection in the folder object.
Catch the transition from using timestamps to sequences transparently.

If the last syncstamp is VERY MUCH greater than then requested sequence,
assume this is a timestamp -> sequence transition and throw a stale state
exception.
Better member name.
@since
Need to catch this exception in GETITEMESTIMATE also.