Those were workarounds to passing a comma to a macro, but there are ways
around it. The simplest is to just use variadic macros; another, which
has been applied to Q_DECLARE_METATYPE for a long time, is to define an
alias to the thing you're trying to use.
Change-Id: Ie4bb662dcb274440ab8bfffd17097fbf0c53eabc
Reviewed-by: Marc Mutz <marc.mutz@qt.io>