[FileAPI] Fix Blob Origin (#20)

This issue is to fix Blob URL's origin, based largely on bugs filed on HTML.

Currently, File API has this:

"The origin of a Blob URL must be the same as the effective script origin specified by the incumbent settings object at the time the method that created it -- either URL.createObjectURL or URL.createFor -- was called."

This should be much better.


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Reply to this email directly or view it on GitHub:
https://github.com/w3c/FileAPI/issues/20