This is a preliminary change for COEP merging to HTML and fetch specs.
We will use the serialization multiple times both in the HTML spec and
the fetch spec, so defining the operation here will be benefitial.

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Integrate CORP and COEP

This is part of the introduction of COEP
(whatwg/html#5454). The CORP check now takes
COEP into account. Also, responses coming from service workers
are checked.

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Update fetch.bs

Co-authored-by: Domenic Denicola <d@domenic.me>
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Update fetch.bs

Co-authored-by: Domenic Denicola <d@domenic.me>
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fix

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fix

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fix

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fix

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fix

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fix

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fix

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fix

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fix

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fix

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fix

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fix

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fix

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fix

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Update fetch.bs

Co-authored-by: Anne van Kesteren <annevk@annevk.nl>
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Update fetch.bs

Co-authored-by: Anne van Kesteren <annevk@annevk.nl>
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fix

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fix

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fix

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fix

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fix