Embedding a QWidget in a window container (via its windowHandle())
may cause crashes, e.g. during drag & drop and when the application
goes out of scope.
If a QWidget->windowHandle() is attempted to be embedded in a window
container, return the pointer to the widget instead of creating a
container.
Add an autotest.
Update documentation.
[ChangeLog][QtWidgets][QWindowContainer] If createWindowContainer()
is called with a QWidgetWindow argument, return pointer to the
widget instead of new container.
Pick-to: 6.7
Fixes: QTBUG-119113
Change-Id: Id052a03be13adce05bbd025d86270d265dfb662e
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>
b9ee6d3b2e