This allows to select device when multiple devices are connected.

R=machenbach@chromium.org, tmrts@chromium.org

Bug: chromium:893593
Change-Id: I3dfd8b98251f613f5c93d29acd5035b236731ea6
Reviewed-on: https://chromium-review.googlesource.com/c/1452441Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Sergiy Belozorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59388}