chromite: Raise error message when devserver cannot start.
Raise DevserverCannotStartError when devserver cannot start on remote
host.
BUG=chromium:718532
TEST=Provision a DUT which had an old version of ChromeOS with local
autotest. Ran cros flash.
Ran unittest.
Change-Id: I7fe1de627b20ba15ce7372ba8769629327845ad9
Reviewed-on: https://chromium-review.googlesource.com/500047
Commit-Ready: Xixuan Wu <xixuan@chromium.org>
Tested-by: Xixuan Wu <xixuan@chromium.org>
Reviewed-by: Xixuan Wu <xixuan@chromium.org>
2 files changed
