Mark connect-src-beacon-allowed.sub.html flaky.

Fails on WebKit Linux Trusty Leak regularly.

TBR=andypaicu@chromium.org,mkwst@chromium.org

No-Try: true
Bug: 651742
Change-Id: I4d8adfc2f8afee4e3ffdd8c8006faa5e34cff978
Reviewed-on: https://chromium-review.googlesource.com/731990
Reviewed-by: Trent Apted <tapted@chromium.org>
Commit-Queue: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#510713}
1 file changed