Bug 1090562 - [Rocketbar] Implement transitions again

https://bugzilla.mozilla.org/show_bug.cgi?id=1090562
crap, probably forgot to submit this comment during the first review round.

But I'd like to bring back some of the original global-search-request tests with `callOrder` assertions. They where removed in https://github.com/mozilla-b2g/gaia/pull/22277/files