It is possible to do this for example:
QVariant v = QVariant::fromValue<MyCustomQObject*>();
QObject *object = v.value<QObject*>();
This means that if a QVariant contains a pointer to a QObject
derived type, third parties can extract a QObject* and use its
properties without knowing the concrete type.
This is a source compatible change.
Change-Id: Iee9a9437e99cc2f40d1a4bfea47275482ef7161f
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@nokia.com>