Fix css_checker.py directory exemption path.

Fix css_checker.py directory exemption path.

R=samarth@chromium.org,jeremycho@chromium.org
BUG=222642
(kinda)
TEST=none
NOTRY=true

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=195342

[Dan Beam, 2013-04-19 23:45:16]

could either of you stamp?

[samarth, 2013-04-19 23:46:57]

lgtm

Thanks Dan! I was actually just about to send you this change :)

FYI, this will be fixed with Jered's pending "iframe" change that obviates the
need for this CSS class (https://codereview.chromium.org/13375003/).

[commit-bot: I haz the power, 2013-04-19 23:50:55]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dbeam@chromium.org/13879015/1

[commit-bot: I haz the power, 2013-04-19 23:51:41]

Change committed as 195342