Add UseCounters for NamedNodeMap functions

Add UseCounters for NamedNodeMap functions

This is in order to help determine which of these need to be kept in the
DOM spec, since it looks like some of them will be needed:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=21986

BUG=none
NOTRY=true

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=169969

[eseidel, 2014-03-25 17:48:07]

lgtm

Great.

[commit-bot: I haz the power, 2014-03-25 17:48:14]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/philipj@opera.com/211363003/1

[commit-bot: I haz the power, 2014-03-25 18:10:00]

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

[commit-bot: I haz the power, 2014-03-25 18:10:00]

Try jobs failed on following builders:
  tryserver.blink on win_blink_rel

[philipj_slow, 2014-03-25 18:16:10]

The CQ bit was checked by philipj@opera.com

[commit-bot: I haz the power, 2014-03-25 18:16:19]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/philipj@opera.com/211363003/1

[commit-bot: I haz the power, 2014-03-25 18:16:35]

Change committed as 169969