Make sure the email address is focused when the dialog starts up.

* The input element was not being focused because we prematurely said that the dialog was in the enterEmailState.
* Fix the failing QUnit test when it is run in isolation.

fixes #3424
Fix IE8 putting the dialog behind its parent window.

fixes #3423
Merge pull request #3432 from mozilla/issue_3424_no_focus

Make sure the email address is focused when the dialog starts up.