Not really, no. Despite the past, I doubt China really are happy with this, not with their standing in the world ever increasing and really beginning to threaten America's dominance around the globe. Why would they still let this go on? What reason to prop up NK than their mistrust of America's intentions?
It's no coincidence, IMO, that NK are really beginning to test the boundaries considering who is in charge of the usa right now, his ridiculous spouting on social media and not to mention America isn't exactly trusted around the world anyway.