[CrOS MultiDevice] Move ProximityAuth logging to MultiDevice.

The MultiDevice component is the correct location for shared
multi-device code.

Bug: 912743
Change-Id: Ie66b135d889c89edad8371ef5ed3a4facec6fd6b
Reviewed-on: https://chromium-review.googlesource.com/c/1380555
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Ben Wells <benwells@chromium.org>
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#617328}
149 files changed