config_service: use == for sentinel value

config_service: use == for sentinel value

I forgot to upload this change to
https://codereview.chromium.org/2931673003

TBR=sergeyberezin@chromium.org
BUG=730832
Review-Url: https://codereview.chromium.org/2934783004
Committed: https://github.com/luci/luci-py/commit/11c952f68eeb28691033eaf9d4057f9a190797ed

[nodir, 2017-06-12 21:04:33]

The CQ bit was checked by nodir@chromium.org

[commit-bot: I haz the power, 2017-06-12 21:04:40]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-06-12 21:07:30]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1497301473992630, "parent_rev":
"a24b2b14dc50bd7b711f2ca93ffb481becb15e89", "commit_rev":
"11c952f68eeb28691033eaf9d4057f9a190797ed"}

[commit-bot: I haz the power, 2017-06-12 21:07:33]

Description was changed from

==========
config_service: use == for sentinel value

I forgot to upload this change to
https://codereview.chromium.org/2931673003

TBR=sergeyberezin@chromium.org
BUG=730832
==========

to

==========
config_service: use == for sentinel value

I forgot to upload this change to
https://codereview.chromium.org/2931673003

TBR=sergeyberezin@chromium.org
BUG=730832

Review-Url: https://codereview.chromium.org/2934783004
Committed:
https://github.com/luci/luci-py/commit/11c952f68eeb28691033eaf9d4057f9a190797ed
==========

[commit-bot: I haz the power, 2017-06-12 21:07:34]

Committed patchset #1 (id:1) as
https://github.com/luci/luci-py/commit/11c952f68eeb28691033eaf9d4057f9a190797ed