Code review comment for lp://qastaging/~sergiusens/nuntium/select_that

My go-fu is bad, but I don't see the service notifying when the PreferredContext property changes.

It's also problematic that the property sometimes is available and sometimes it's not. I can work around this in the bindings, but I need two things:

1) instead of adding/removing the property, have a "not set" value (empty string would do just fine) and have the interface report PropertyChanged signal each time the property is modified
2) or add a straight signal PreferredContextChangede when you add or remove the property.

Current implementation makes it really difficult (or almost impossible) to write bindings on Qt.