Bug 974292 - [Email][V1.3&V1.4] Tapping the Done button of mail settings page redirects to a blank page

This is a side effect of this change:

https://github.com/mozilla-b2g/gaia/commit/f1053cc117ebf147dad7801d32746b375b5ec599#diff-3

where `Cards.removeCardAndSuccessors(this.domNode, 'animate', 1);` was changed to `Cards.removeCardAndSuccessors(this.domNode, 'animate');`

By leaving out the "how many cards" it meant "this card and all cards after it". However, since the folder_picker is added **before** message_list in the stack, it means that all the account cards are inserted between folder_picker and message_list. So when the removeCardAndSuccessors removed the progress card, it also removed message_list.

Restoring the 1 arg fixes it. I apologize for letting this slip past before, as I had it in my head that removeCardAndSuccessors defaulted to just that one card if no arg so I did not comment on it when I saw the change.