Many of their developers use Chromebooks, I believe. Code is not allowed to be stored locally on mobile devices so they use Chromebooks and SSH (or any other laptop and SSH).
Additionally, I think that going forward on-site interviews at Google will use Chromebooks to type code up, rather than white-boarding (which makes me sad, but I suspect will make all the people who hate white-boarding a lot happier).
And this is why I am always suspicious of an IDE. This sounds like a really nice way to talk to a Linode to develop on.