This allows people to use repo to manage the checkout instead of gclient.
This helps when you're used to the standard repo+gerrit workflow that the
Android & Chromium OS projects use.
Change-Id: I8b720e7995af2a1a8c9ce2ee9aa6c2638441b4a1
Reviewed-on: https://chromium-review.googlesource.com/379736
Reviewed-by: Mark Mentovai <mark@chromium.org>