D6630: [kstyle] Do not delete the Surface for a QWindow

[Martin Flöser]

graesslin added a reviewer: mart.

REPOSITORY
  R31 Breeze

REVISION DETAIL
  https://phabricator.kde.org/D6630

To: graesslin, #plasma, mart
Cc: plasma-devel, ZrenBot, progwolff, lesliezhai, ali-mohamed, jensreuterberg, 
abetts, sebas, apol, mart, lukas