[web-payments-browser-api] Step 6 of the payment flow is incomplete/unclear (#5)

Step 6.2 is incomplete and so it's unclear if the payment app will use a standard interface to talk to the 3rd party.

The phrase "payment app forwards the request and selected payment instrument (if previously selected) to the 3rd party for approval" suggests that 3rd parties should all expect to receive a standard payment request object.

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Reply to this email directly or view it on GitHub:
https://github.com/WICG/web-payments-browser-api/issues/5