[spec-reviews] Review FormData additions in XHR (#87)

The FormData interface grew some additional methods beyond the historical `append`, which allow the keys/values to be inspected, modified, and so forth:

https://xhr.spec.whatwg.org/#interface-formdata

These have shipped (apart from the iterator?) in Firefox. We have them implemented behind an experimental flag in Chrome and are looking for any feedback from the TAG before we ship.

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Reply to this email directly or view it on GitHub:
https://github.com/w3ctag/spec-reviews/issues/87