Add support to chromeos test runner for running tests on devices.

Adds a "--use-vm" option (when using VMs) and a "--device" option (when
using real devices.)

Bug: 866062
Change-Id: Ic8fd34f9c34e5bc8b42b8e900220d30a8b19e645
Reviewed-on: https://chromium-review.googlesource.com/c/1380332
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#617222}
3 files changed