Fixes: NB#240412 - [TASK] Optimize MWidget::setVisible()
Fixes: NB#240412 - [TASK] Optimize MWidget::setVisible()

RevBy: Daniel d'Andrada
MergeRequest: 1626

Details: If we are already explicitly hidden, early out.
If current visibility has changed or we're explicitly hidden we must change the visibility.

nemomobile-graveyard/libmeegotouch,nemomobile-graveyard/libmeegotouch,nemomobile-graveyard/libmeegotouch,nemomobile-graveyard/libmeegotouch,nemomobile-graveyard/libmeegotouch,nemomobile-graveyard/libmeegotouch