Bug 1041565 - Setting for toggling pseudolocales

https://bugzilla.mozilla.org/show_bug.cgi?id=1041565
I like that but I'm not sure how I can query the children of the `select` once I have a reference to `Marionette.Element` which represents it.  Any ideas?  Maybe [executeScript](http://mozilla-b2g.github.io/marionette-js-client/api-docs/classes/Marionette.Client.html#method_executeScript)?