@dgarrett - who can make this change?

Any Chromite developer is suitable.

Marking non-FixIt because we are having issues creating custom PreCQ build configs. So.... waiting until after we get the signer PreCQ builder working.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/a55dffa06e7606c359d5c212195bcb2d919e401f

commit a55dffa06e7606c359d5c212195bcb2d919e401f
Author: Don Garrett <dgarrett@google.com>
Date: Tue Feb 21 22:07:46 2017

chromite-pre-cq: Create a chromite-pre-cq builder.

This CL creates a new builder to run the chromite network unittests,
which are expensive and don't need to be run per-board in the CQ.

I don't expect the tests to pass until crbug.com/682381 is fixed, but
this builder hasn't been added to COMMIT-QUEUE.ini yet.

BUG=chromium:674390
TEST=run_tests

Change-Id: Ibd5fe9df279a9abef9730124bfb74aef88f77a16
Reviewed-on: https://chromium-review.googlesource.com/441306
Commit-Ready: Don Garrett <dgarrett@chromium.org>
Tested-by: Don Garrett <dgarrett@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>

[modify] https://crrev.com/a55dffa06e7606c359d5c212195bcb2d919e401f/cbuildbot/commands.py
[modify] https://crrev.com/a55dffa06e7606c359d5c212195bcb2d919e401f/cbuildbot/chromeos_config.py
[modify] https://crrev.com/a55dffa06e7606c359d5c212195bcb2d919e401f/cbuildbot/config_dump.json
[modify] https://crrev.com/a55dffa06e7606c359d5c212195bcb2d919e401f/cbuildbot/stages/test_stages.py
[modify] https://crrev.com/a55dffa06e7606c359d5c212195bcb2d919e401f/cbuildbot/waterfall_layout_dump.txt
[modify] https://crrev.com/a55dffa06e7606c359d5c212195bcb2d919e401f/cbuildbot/builders/test_builders.py

 Issue 660455  has been merged into this issue.

On hold for now.

This should include:
  lib/cidb_integration_test --network