Prevent changing the primary screen when it doesn't have a view yet

Review Request #125693 - Created Oct. 18, 2015 and submitted

David Kahles

When a new primary output gets connected, it's possible that
primaryOutputChanged() is called before addOutput(). When addOutput()
was called afterwards, this led to two DesktopViews on the same
screen. This raised an assert in screenInvariants().
Solve this by not doing anything in primaryOutputChanged() when the new
primary output is not used for a DesktopView yet.

Plasmashell doesn't hit an assert in screenInvariants() after addOutput() when connecting a new screen set as primary screen.
(That doesn't mean it works, but at least there's a bug less)

Aleix Pol Gonzalez
David Kahles
Review request changed

Status: Closed (submitted)

Change Summary:

Submitted with commit 61828df89f3e7319bdc7024409804b51c0ba5b68 by David Kahles to branch master.