I cannot find any link to a repository with that ported library. I can't imagine why you wouldn't share this exciting port, unless of course the code is not that great? And as a sidenote, why would you ever hijack the up/down cursor keys on a web page? There are still people out there on actual computers which use them for scrolling.
There are also people who will give up on the article when they realize they can't scroll with the arrow keys.