Update leak expectations for new ServiceWorker tests

(We're not sure if they're real or not yet, but apprently they
seem to coming from the same cause)

BUG=364390
TBR=kouhei@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/302633011

git-svn-id: svn://svn.chromium.org/blink/trunk@174946 bbb929c8-8fbe-4397-9dbb-9b2b20218538