The native implementation uses NSAlert, making a best effort to map the
QMessageBox properties to the native dialog, falling back to the cross
platform non-native dialog if the discrepancy is too big.
The initial implementation focuses on the current state of the
native dialog helper "protocol", but there's room for improvement
here, which would allow even more dialog types and properties to
be native.
[ChangeLog][macOS] Message boxes such as QMessageBox now follow
the platform look and feel by using native dialogs if possible.
Change-Id: I4da33f99894194a7b301628cd1fbb44d646ddf18
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
a47c7a9826