GitLab

This CL added code to show an icon for connected device in the
chooser, and added "- Paired" text after the device name if the
device is paired.

I uploaded some screenshots from ChromeOS in the issue page.

BUG=543466

Review-Url: https://codereview.chromium.org/2330593002
Cr-Commit-Position: refs/heads/master@{#418916}