[Docs] device mode in devtools docs topnav

[Docs] device mode in devtools docs topnav

BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=290737

[mkearney1, 2014-08-18 18:39:56]

lgtm with a request to see a staged version to double-check.

[paulirish, 2014-08-19 19:33:03]

This is due to docserver preview script not understanding my clone of the git
repo. I'm going to commit anyway, as the diff is clear and simple. 

I'll sort out my clone separately.

thx!

[paulirish, 2014-08-19 19:33:09]

The CQ bit was checked by paulirish@chromium.org

[commit-bot: I haz the power, 2014-08-19 19:34:36]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/paulirish@chromium.org/458643002/1

[commit-bot: I haz the power, 2014-08-19 19:34:37]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-08-19 19:34:38]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[paulirish, 2014-08-19 20:02:01]

@kalman, I need a rubberstamp on this baby.

[not at google - send to devlin, 2014-08-19 20:03:33]

lgtm

[paulirish1, 2014-08-19 20:28:48]

The CQ bit was checked by paulirish@google.com

[commit-bot: I haz the power, 2014-08-19 20:29:51]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/paulirish@chromium.org/458643002/1

[commit-bot: I haz the power, 2014-08-20 02:59:48]

Committed patchset #1 (1) as 290737