SetupWizard: Handle both restore scenarios.

  If a user logs into Google's SetupWizard with their
  gmail account, they need to be prompted with a restoration
  picker -- otherwise, if they have a valid restoreToken
  and restoreAccount, we can assume that they came from a
  Tap & Go scenario and begin restoring as needed.

Change-Id: Ifa9ce978822f365996a509edeb3023001a07be84
TICKET: CYNGNOS-2233
(cherry picked from commit 6baab03b)