Bug 1057670 - Change title displayed in collapsed rocketbar within apps

https://bugzilla.mozilla.org/show_bug.cgi?id=1057670
Yeah, looks like we have a test for that here: https://github.com/mozilla-b2g/gaia/blob/master/apps/system/test/marionette/browser_meta_application_name_test.js

I'll add another case to that one to verify this as well.