How does Google Chrome Instant Omnibox work?

How does omnibox instant in Google Chrome 9 work ?

I enabled developer panel an开发者_JS百科d checked, but didn't find any XHRs being fired... Is the Omnibar hidden from developer panel ?

This part is done in C++, so you won't see it in the developer panel; you can use Google Codesearch for Chromium to view the Chromium source code. Of interest may be InstantController and TemplateURLFetcher. It's not the easiest code to follow, because it is written in the asynchronous style (the instant bits register an observer that gets invoked when the suggest URL has been fetched).