We would like Fennec's locale options to be decoupled from the underlying OS locale selection. That involves: * A UI for making an election. Bug 917480, with reuse from Bug 881510. * Facilities for switching locales, either the hard way (restarting the browser) or the soft way (runtime swap). This involves solving some performance questions, too. * Ideally: facilities for downloading locales at runtime, so we don't have to ship them all. * Reach goal: l20n support. If we're moving outside the realm of R.java, we should target enough modularity that we can switch to Mozilla's next-gen tooling. This is a meta bug to track these components.