[paymentrequest] Should the web page be able to provide status information before calling complete() (#32)

Once the user has accepted the payment request, the `state` of `PaymentRequest` moves to `accepted` and the Promise returned from `show()` is resolved. The web page is responsible for processing the `PaymentResponse` and then calling `complete()` with a success or failure value. During this time the user may be wondering about what is happening. Should we provide a mechanism for the web page to provide message text back to the user agent about what it is doing to show progress?

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Reply to this email directly or view it on GitHub:
https://github.com/WICG/paymentrequest/issues/32