Add missing locale parameter to promo service.

Add missing locale parameter to promo service.

The locale parameter (hl=) has been broken by the componentization of
web_resource, and is now always empty.
This CL restores the right behavior.

BUG=454485
Committed: https://crrev.com/df20b77a99b3542d7b5fe56ad7f7d9b3a88b2f33
Cr-Commit-Position: refs/heads/master@{#314334}

[droger, 2015-02-03 13:55:33]

Patchset #1 (id:1) has been deleted

[droger, 2015-02-03 14:01:04]

droger@chromium.org changed reviewers:
+ rsesek@chromium.org

[Robert Sesek, 2015-02-03 15:01:39]

LGTM. Thanks for the quick fix!

[Robert Sesek, 2015-02-03 15:01:40]

LGTM. Thanks for the quick fix!

[droger, 2015-02-03 15:02:17]

The CQ bit was checked by droger@chromium.org

[commit-bot: I haz the power, 2015-02-03 15:02:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/900633002/20001

[commit-bot: I haz the power, 2015-02-03 15:06:13]

Committed patchset #1 (id:20001)

[commit-bot: I haz the power, 2015-02-03 15:07:32]

Patchset 1 (id:??) landed as
https://crrev.com/df20b77a99b3542d7b5fe56ad7f7d9b3a88b2f33
Cr-Commit-Position: refs/heads/master@{#314334}