Plugins: Mark the Silverlight plugin test as non-flaky - has not failed in 500 test runs.
Plugins: Mark the Silverlight plugin test as non-flaky - has not failed in 500 test runs.

BUG=22666
TEST=none
Review URL: http://codereview.chromium.org/2000008

git-svn-id: http://src.chromium.org/svn/trunk/src@46861 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: f46bef81461edbac7f660db6ecf173bf45368f93
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