ServiceWorker: Reject registration access from script created documents
This fixes DCHECK failure (BadMessageReceived on release) when attempting
to register/unregister/lookup SW from a document in an iframe using
frame.contentDocument.write(...).
The origin check should be done against the iframe's origin, which is the
same as its container document's origin. But as a quick fix for the crash,
this patch rejects registration access from such iframe documents.
BUG=436034,439696
Review URL: https://codereview.chromium.org/
798453003
Cr-Commit-Position: refs/heads/master@{#307874}