Bug 1049916 - Create Firefox Accounts smoke tests to validate user authe...

...ntication R=spenrose
I don't quite follow your comment here, but if we have the same exact code in multiple tests, I think it'd be best to extract it out to a lib method. For instance, what if we add or remove a screen from the FxA flow? It would be better to have one place to update all the tests that exercise a given flow.

I've gotten super busy this week and neglected this review, sorry. I'll find some time on the calendar tomorrow to discuss this stuff :-)