Also, personally I would like to skip the "No patches were provided; are you sure you want to just run a build of master? (yes/No)?" query in this case. (Avoidable with --yes, but then I worry about what else I might be answering 'yes' to...)

Do you also need --chrome_rev? I have no idea what it means, but it seems related.

I've never used it. The docs say:

Revision of Chrome to use, of type [tot|latest_release|stable_release|local|spec]

That doesn't seem particularly helpful; if I want to test with a different chrome I will always be able to (and probably want to) specify a specific git revision id.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/f7544a7a90d4f194583540ea1d363d9bdffcaff7

commit f7544a7a90d4f194583540ea1d363d9bdffcaff7
Author: Don Garrett <dgarrett@google.com>
Date: Tue Nov 07 23:25:20 2017

cros_tryjob: Add --chrome_version passthrough option.

--chrome-version is used by Gardeners, so put it back.

BUG= chromium:781905 
TEST=run_tests

Change-Id: I14fdc4b4eeca8eb04fe3d51793b419bb16789c26
Reviewed-on: https://chromium-review.googlesource.com/755841
Commit-Ready: Don Garrett <dgarrett@chromium.org>
Tested-by: Don Garrett <dgarrett@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>

[modify] https://crrev.com/f7544a7a90d4f194583540ea1d363d9bdffcaff7/cli/cros/cros_tryjob_unittest.py
[modify] https://crrev.com/f7544a7a90d4f194583540ea1d363d9bdffcaff7/cli/cros/cros_tryjob.py