[paymentrequest] Consider allowing a web site to provide a label for the "Buy" or "Checkout" button (#46)

It may help users understand what they are accepting if the web site is able to label the "accept" button. For example, if a user is about to "Buy" something, "Reserve" something, "Subscribe" to something, etc.

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Reply to this email directly or view it on GitHub:
https://github.com/WICG/paymentrequest/issues/46