[CrOS MultiDevice] Fix multi-device setup UI in OOBE.

OOBE support for multi-device setup broke due to a transition from the
"full" JS bindings to the smaller "lite" JS bindings.

This CL updates the first run (i.e., OOBE) flow to use the correct type
provided by the lite bindings. It also adds a Closure compile BUILD
target to ensure that this does not regress.

Bug: 946743
Change-Id: Iaa2f879bb57bf26deebfc8e29baae0a9bd78c2fc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1542152
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Commit-Queue: Alexander Alekseev <alemate@chromium.org>
Auto-Submit: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#645454}