Add a Mac suppression for a sporadic leak.
Add a Mac suppression for a sporadic leak.

BUG=17297
TEST=Greener Mac valgrind unit_test bot

Review URL: http://codereview.chromium.org/155806

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@21115 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser