It seems to me China would generally be in favour of this. They're a large country with large internal consumption, and they would rather some of this money goes into their coffers than somewhere else. Generally, fiscal paradise are small countries which have little to lose by lowering taxes (to local business), and a lot to gain by attracting revenues from bigger countries.

China's corporate taxes are much higher than 15%, so it's not like they would be directly affected by this. They might oppose the plan (I have no idea), but it's unlikely to be on an economical aspect of that's the case.