I think countries will break up and new borders established, eventually, and might take on the old name but be a different country, with a White majority. I don't believe any currently existing save maybe some of the Scandinavian countries, maybe, might keep a White majority as is. Once there's too many non-whites in they simply outbreed you, or if you're closely enough related like with Hispanics you also get absorbed bit by bit. Whites end up a minority in either case.