Remove the queued states mechanism from ServiceWorker

It can instead be handled by WebServiceWorkerImpl for better clarity
about who is the source of truth. That will happen in a subsequent
Chromium patch: https://codereview.chromium.org/255813003/

This patch is a follow-up to Blink r172459:
https://codereview.chromium.org/247263010

BUG=365252

Review URL: https://codereview.chromium.org/256723002

git-svn-id: svn://svn.chromium.org/blink/trunk@172682 bbb929c8-8fbe-4397-9dbb-9b2b20218538