Mac: Suppress mysterious valgrind error from after a bot restart.
Mac: Suppress mysterious valgrind error from after a bot restart.

BUG=42593
TEST=Mac Valgrind unit_tests goes green
TBR=wtc
Review URL: http://codereview.chromium.org/1692010

git-svn-id: http://src.chromium.org/svn/trunk/src@45658 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: e762f5ec446bb915fe01f39b127e6a70272ec3aa
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