autotest: Run stumpy cell field test in a whiny matrix friendly way

Turns out that whiny matrix doesn't know about pools, so its very hard
to compare the results for a suite on one pool versus another pool.
Instead, introduce a new suite and run that.

BUG=chromium:241617
TEST=None

Change-Id: Ie727931f798669a17f3340c84d62b68b3c7f67aa
Reviewed-on: https://gerrit.chromium.org/gerrit/58235
Tested-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Alex Miller <milleral@chromium.org>
Commit-Queue: Christopher Wiley <wiley@chromium.org>
4 files changed