This patch introduces support for the WinRT UI languages API.
We are using the Win32 API to get the list of preferred languages when
the system locale is used. However, this API returns an incomplete
list.
As Qt 6 supports Windows 10 and above, we can make use of the WinRT
API, if it's supported by the compiler. This API returns the full list,
as reported by the Windows system itself.
Note however, that this API can't be used with Clang and MinGW, so
we still have to fall back to Win32 API for these compilers. We also
do it if WinRT API returns an empty list of languages for some reason.
Fixes: QTBUG-94341
Pick-to: 6.2
Change-Id: I1d23c68d2ec298ae7835d0d18718876ff041aede
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
51e8d3592a