These were invented primarily to test the multibyte path handling
patch on Windows. How it turns out by PR #2105, some test issues
on some filesystems are possible. Particularly HFS is configurable
to use different ways to save filenames, see
https://developer.apple.com/library/mac/qa/qa1173/_index.html
This makes it impossible to test the filenames byte wise, while
the results are still correct. There are still several other tests
using UTF-8 file names spread over other extensions. So far no
false positives are to see, they don't need to be touched.
596f488e06