Own USB device manager in the Device Service.

Bug: 699790
Change-Id: I371875d657b35622695dc9cb5c33a2372e97c600
Reviewed-on: https://chromium-review.googlesource.com/c/1253414
Commit-Queue: Donna Wu <donna.wu@intel.com>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#598348}
7 files changed