Fix for clang chromium-style in promo.

Fix for clang chromium-style in promo.

./chrome/browser/web_resource/notification_promo_mobile_ntp.h:21:1:
error: [chromium-style] Complex class/struct needs an explicit
out-of-line destructor.  class NotificationPromoMobileNtp {

BUG=


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=154576

[aruslan, 2012-08-31 23:38:52]

Please take a look, thanks!

[achuithb, 2012-08-31 23:55:32]

lgtm

[commit-bot: I haz the power, 2012-08-31 23:58:06]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/aruslan@chromium.org/10919049/1

[commit-bot: I haz the power, 2012-09-01 02:25:00]

Change committed as 154576