QWindows11Style inherits from QWindowsVistaStyle for which StyleSheet
theming is deactivated. QWindows11Style draws most elements with
QPainter and should therefore be able to use overrides by StyleSheets.
This patch checks, whether QWindows11Style is used and enables the
theming by declaring it not to be a QPixmap based style. Further drawing
routines for QComboBox, QPushButton and QLineEdit are now drawing always
the base background and when they are hovered a alpha mask is used to
overdraw the elemens to create a highlight effect.
Fixes: QTBUG-124286
Pick-to: 6.7 6.7.1
Change-Id: I65436493bc2b1572c0d9423a066caea3ba9e1459
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>
b733d31f27