The Qt::WA_DontShowOnScreen widget attribute does not limit whether a
widget will be created (have a QWindow and corresponding QPlatformWindow).
It only limits whether the widget will be shown.
As a result, we need to respect and process incoming events on a QWindow
level, just as any other window. Any considerations that may apply because
of WA_DontShowOnScreen should happen further down in the event delivery.
For example for the issue in 74aae00a4e8e70845e8092abbefa7830c386e66b,
where QWidgetWindow::handleExposeEvent() cleared the WA_Mapped flag which
was set by QWidgetPrivate::show_sys().
Change-Id: I187ebe14ea84538a3715f1d09fb1ba1ce93fcc82
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
11214f4c42