I haven't read through COPPA, but I believe that Google, as a US company, has to abide by COPPA restrictions, regardless of where they're storing data. (It might even apply to non-US users...) As the user above pointed out, COPPA is really, really hard to 'get around.'
I've always been confused by this. Does "as a US company" mean that it's HQ is in the US? Or that it is incorporated in the US? Or just that it does business in the US?