Fix some status notifier items not appearing

Summary:
Set the initial values for all the things
This is important as Plasma::DataModel has an unsolvable bug
When it gets data with a new key it tries to update the QAIM roleNames
From QML this achieves absolutely nothing as there is no signal to tell
QQmlDelegateModel to reload the roleNames in QQmlAdapatorModel
No matter if the row changes or the model refreshes
This means it does not re-evaluate what bindings exist (watchedRoleIds)
and we get properties that don't bind for this or any future SNI.

The main source of this problem is syncStatus can occur before
refreshCallback; but whilst that's easy to guard against, there's still
multiple if{} blocks that don't set various keys in refreshCallback()
which would all need changing too. This seemed cleaner and easier to
manage.

BUG: 366283
BUG: 367756

Reviewers: Plasma, mart

Reviewed By: mart

Subscribers: broulik, plasma-devel

Tags: Plasma

Differential Revision: https://phabricator.kde.org/D2613