[fetch] Behavior unspecified with multiple headers with same name (#190)

https://fetchspecwhatwgorg/#headers-class could be more specific in these two cases:
1) Does delete(name) delete all headers with the given name, or just the first such header?  If the former, should it be called deleteFirst? If the latter, should there be a deleteAll?
2) Does set(name, value) overwrite the first header with the given name if there is one?  Should it leave the other headers with the given name untouched? If there isn't one, does it append it at the end?

Sorry, I'm new to working with whatwg  How would I go about changing this or suggesting tests for a test suite?

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/issues/190