Mark NewTabUITest.UpdateUserPrefsVersion as flaky.
Mark NewTabUITest.UpdateUserPrefsVersion as flaky.

BUG=51726
TEST=none

Review URL: http://codereview.chromium.org/3140006

git-svn-id: http://src.chromium.org/svn/trunk/src@55628 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: d46658f8c828d7b08033fe55c7995b6050fae4f7
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