Add a suppression for a leak the Mac UI tests get when plugins are first loaded.
Add a suppression for a leak the Mac UI tests get when plugins are first loaded.

BUG=none
TEST=Fewer leaks on the Mac valgrind UI test bots
Review URL: http://codereview.chromium.org/155190

git-svn-id: http://src.chromium.org/svn/trunk/src@20156 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 4921f2a74f824d0c75ec21140b935031f6ce576c
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