Popular sites on the NTP: Add Finch params for country and version

Popular sites on the NTP: Add Finch params for country and version
so that we can specify them separately (e.g. explicitly set a version, but
use the client-side country detection).

BUG=516618
Committed: https://crrev.com/b28d6505698940eb2886540c8e877643c7c8d801
Cr-Commit-Position: refs/heads/master@{#350151}

[Marc Treib, 2015-09-10 13:17:34]

treib@chromium.org changed reviewers:
+ bauerb@chromium.org

[Bernhard Bauer, 2015-09-10 13:35:33]

lgtm

[Marc Treib, 2015-09-22 13:45:28]

The CQ bit was checked by treib@chromium.org

[Marc Treib, 2015-09-22 13:45:28]

The patchset sent to the CQ was uploaded after l-g-t-m from bauerb@chromium.org
Link to the patchset: https://codereview.chromium.org/1331113002/#ps40001
(title: "rebase")

[commit-bot: I haz the power, 2015-09-22 13:45:31]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1331113002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1331113002/40001

[commit-bot: I haz the power, 2015-09-22 14:28:57]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-09-22 14:30:33]

Patchset 3 (id:??) landed as
https://crrev.com/b28d6505698940eb2886540c8e877643c7c8d801
Cr-Commit-Position: refs/heads/master@{#350151}