If a QObject is returned from a method call, the QML engine takes
ownership of it and it needs to be deleted by the garbage collector. Our
generated C++ code so far did not actually take ownership of the object
and thereby caused it to leak.
Pick-to: 6.10 6.9 6.8
Fixes: QTBUG-138919
Change-Id: I7bd57b3612bf4b98937756e8a7a7c03aff1c9b32
Reviewed-by: Olivier De Cannière <olivier.decanniere@qt.io>
Ulf Hermann