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Summary:

Keep it as before on the desktop to be consistent with the other plasmoids

Test Plan: run plasmashell with/without QT_QUICK_CONTROLS_MOBILE

Reviewers: Plasma, VDG, broulik

Reviewed By: Plasma, broulik

Subscribers: broulik, KonqiDragon, plasma-devel

Tags: Plasma

Differential Revision: https://phabricator.kde.org/D24934