Oops, #0 should say  issue 629357 

Enterprise Autotest Plan Q3 2016: http://go/cros-ent-atp-16q3

CL in progress: https://chromium-review.googlesource.com/#/c/363584

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/autotest/+/f00a5b79efbf3674d39ed2a76cb95ca0436c99b2

commit f00a5b79efbf3674d39ed2a76cb95ca0436c99b2
Author: Scott Cunningham <scunningham@chromium.org>
Date: Wed Jul 27 01:36:35 2016

Remove self.mode var, and mode parameter from --args

We have no need for mode 'all' and 'list'. When 629357 is done, all
cases will run individually (like they do in 'single' mode today),
so we have no need of 'single' mode. Also, 'by_case' and 'by_value'
should collapse into the same case.

Thus, we can safely remove the self.mode variable and command line
argument entirely.  This change will obviate the run_once_impl()
function and return us to using run_once() like other autotests.

BUG= chromium:629368 
TEST=Run test_that <IP> on any policy_* test with the following
arguments: none | value=a_valid_value | case=a_valid_case
Also run with env=dm-fake, dm-test, cr-alpha, and prod

Change-Id: I79fa1e8e985c246b3d02b03cadd27314de4a736b
Reviewed-on: https://chromium-review.googlesource.com/363584
Commit-Ready: Katherine Threlkeld <kathrelkeld@chromium.org>
Tested-by: Scott Cunningham <scunningham@chromium.org>
Reviewed-by: Scott Cunningham <scunningham@chromium.org>
Reviewed-by: Katherine Threlkeld <kathrelkeld@chromium.org>

[modify] https://crrev.com/f00a5b79efbf3674d39ed2a76cb95ca0436c99b2/client/cros/enterprise_policy_base.py

No regression of tests running in HW lab. Flakiness is the same. https://wmatrix.googleplex.com/unfiltered?hide_experimental=true&days_back=14&tests=policy_.*