Disable a ui test on valgrind mac, because it is causing the bot to hang.
Disable a ui test on valgrind mac, because it is causing the bot to hang.

BUG=39057
TEST=tree greener
TBR=dhg

Review URL: http://codereview.chromium.org/2502001

git-svn-id: http://src.chromium.org/svn/trunk/src@48760 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: e8ef1658dad7b9a363b8c411e75ae2c64b072fb3
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