All KCMs and KWin core use the BuiltInEffects namespace to find and
interact with the effects. There is no information left in the desktop
file which are of usage. Thus they can be removed.
This effect is controlled by KScreen. It fades out all windows when
KScreen requests this and gives feedback to KScreen once all windows are
faded out. This allows KScreen to adjust the screens in a flicker free
way.
REVIEW: 110661
BUG: 319994
FIXED-IN: 4.11