[ServiceWorker] serviceworker for iframes with srcdoc (#765)

As I understand it `<iframe seamless="seamless" sandbox="allow-same-origin" srcdoc="<img src='/example.png'/>"/>` should load /example.png as if it was on the containing page.

To this end, I feel like the navigation should go via the parent page's service worker's fetch event.

Unfortunately this doesn't work in either Chrome or Firefox because the srcDoc has no `document.URI`, you can see the current behaviour here: https://cdn.rawgit.com/ConradIrwin/2194f982494ba943a4c0/raw/ec0a6d3ebe69e2953e10d049005065de85588fa0/iframe.html

I'm trying to understand if this is a deliberate feature "iframes with srcdoc should not inherit the parent service-worker under any circumstance", or an edge-case that wasn't considered.

My use-case is loading emails into an iframe, I'd like to be able to fetch resources in the emails using the service worker so that I can load attachments as inline images.



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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/765