[ServiceWorker] Step 5.4 of openWindow uses the incumbent settings object, which makes no sense (#695)

This step is running async.  There might not even be an incumbent settings object at this point.

If the intent is to use the origin of the incumbent settings object at the point when openWindow was called, then you need to capture it before going async.

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/695