Also seems I've spotted again that issue when on phone reboot watch is spammed with old messages. Cannot reliable reproduce it but i suspect this happens when
a) rockpoold starts very early
b) at this phase comhistoryd repopulates its events from persistent storage, emitting them on dbus.

Attempted to fix it by filtering out old events. I.e. if timestamp of event is out if timeline window - just ignore it (this actually is proper behaviour which was missing).
And if event is inside window - there two outcomes:
* If event is delivered to pebble and hence exists in persistent storage - will be ignored as duplicate.
* If event was discarded/dismissed/removed - it will be re-delivered to pebble (cant stop this to happen really).