Chrome OS: Integrate Discover PIN setup into First run UI.

Bug: 852553
Change-Id: I215392305eee1555441d5dd66f0bb2908d0f5525
Reviewed-on: https://chromium-review.googlesource.com/c/1250136
Commit-Queue: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Jacob Dufault <jdufault@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599137}
9 files changed