Right now, running telemetry tests on chrome os hardware tests whatever browser is already on the device. We'll eventually want to add cros coverage to the perf waterfall, so we need a way to deploy a locally built chrome/chrome ToT onto the remote device.

A script for this already exists at https://chromium.googlesource.com/chromiumos/chromite/+/master/scripts/deploy_chrome.py

We need an option to telemetry to call this script (either directly or indirectly) before running tests. Maybe something like a --deploy option to telemetry?