Reset bg page badge when wrench menu closes.
Reset bg page badge when wrench menu closes.

BUG=65926
TEST=Install extension with background page, click on wrench menu, see badge, click again, don't see badge

Review URL: http://codereview.chromium.org/5906002

git-svn-id: http://src.chromium.org/svn/trunk/src@69344 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 3ae7230ed9172c7d67596d78fba77cf0960a5126
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser