The article also mentions that "The model benefited the fact that all of Google’s internal applications are already on the Web". I'm just going to assume that means Google employees are using web-based remote access for development. If that's the case then their Chromebooks are really just expensive dumb terminals. We may differ on this but I personally don't see any reason to drop $1k+ on a dumb terminal just to say I own the hunk of plastic I do my job on every day, particularly when my employer will hand me one for free when I start my new job.
Based on that assumption I think you can also reasonably assume permissions around futzing with the needed browser plugins are limited and device compromise is handled how Chromebooks normally handle most problems: wipe and reinstall.