Big thanks to @heyjustyn for finding embedUrl.
Token query flag removed (doesn't seem to be sent in browser anymore).
I'm not sure about the standard for video_id. I'd guess that one should
not change it throughout _real_extract, but I'm not sure of a better way
if we desire to use rrn_id as the video_id (it seems to be the best
identifier).
13d6440717