Will be needed in the KCM to correctly update the UI
There are properties that are related to the overall output state and will never change individually (e.g. id, type, name). Technically modes /may/ change independently of the output (it is possible to add modes in XRandR), but historically we did not support that, so modes were always coupled with the output state as well. I think this is the correct approach to fix a bug, but longterm someone should probably look into what happens when the outputChanged() signal is removed from here and from setModes() as there might be some code listening to it instead of modesChanged().