Linux: add suppression for occasional ui valgrind failure.
Linux: add suppression for occasional ui valgrind failure.

See, e.g., failure here:

<http://build.chromium.org/buildbot/waterfall/builders/Linux%20Tests%20(valgrind)(3)/builds/2168/steps/valgrind%20test%3A%20ui/logs/stdio>

BUG=30870
TEST=green (Linux) valgrind
TBR=slightlyoff@chromium.org, viettrungluu@chromium.org

Review URL: http://codereview.chromium.org/501145

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@35067 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