We cannot convert to QVariant using QMetaType::convert(). But we can
just construct a QVariant with the desired type and data. This will
become an issue once we automatically convert argument types to match
the desired type inside the function.
As a side effect, also allow declaring "var" arguments to functions.
Change-Id: Idc14021d8d85d3d09ee7b7f286de91b56ea02bfd
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>