[fullscreen-api] Allowing AJAX requests when in fullscreen mode

Hello,

I'm working currently on an AJAX web application that uses fullscreen API.
Unfortunately on Google Chrome, when using fullscreen API, each new AJAX
requests, closes fullscreen mode. Only Firefox behaves as expected. I think
it would be a good idea to state in W3C that any AJAX requests shouldn't
break the fullscreen mode. For now solution is to provide an iframe wrapper
for whole app content, but in my opinion it's rather hack than an optimal
solution.

Regards,
Adam Sobaniec