Amends commit 3b541daff7 to deal with
likely subtags being handled as tuples of enum names, rather than as
tuples of their numeric values. The change from names to value went to
6.9 (commit bd5bb70b7c980d737d03db7a9d00b864fa144de0) but isn't picked
back to 6.8 or earlier. However, the type annotations done on 6.9
after that were picked back to 6.8 and I missed this twist in review.
Task-number: QTBUG-129613
Change-Id: I35eb21d26db1ff0537ecaf5e727431a16c6443c4
Reviewed-by: Mate Barany <mate.barany@qt.io>
34f6bf5b7c