Consider having ListView default to Accessible.List role

Many components (like the Controls buttons, sliders etc) set the Accessible role appropriately by default.

ListView does not automatically set a role. The List role has special support in screen readers (or at least orca) – the user is informed that they have entered a list, and the number of items is announced (not quite correctly if not all list entries have their delegate instantiated, but that's a separate issue).

It's possible that not every ListView should be announced this way, but in KDE we constantly find ourself setting the role manually on every single ListView as we work to improve screen reader accessibility (and I can't think off-hand of one where we do not want it).

It might make sense to have ListView default to this to make creating accessible applications simpler, and instead override the cases where the List role is not desired, rather than the other way around