Support fine-grained errors for payment methods

[marcoscaceres]

closes #727

The following tasks have been completed:

• [x] Confirmed there are no ReSpec errors/warnings.
• [ ] Added Web platform tests (link)
• [ ] added MDN Docs (link)
• [ ] added MDN compat data

Implementation commitment:

• [x] Safari - already implemented.
• [ ] Chrome
• [ ] Firefox
• [ ] Edge (public signal)

Impact on Payment Handler spec? See: https://github.com/w3c/payment-handler/issues/306

So we can do, for example:

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Preview | Diff

[marcoscaceres]

On Basic Card side: https://github.com/w3c/payment-method-basic-card/pull/58

[marcoscaceres]

Thanks for checking on status. We have an implementer's call wrt this and other features coming up on the 18th.

[marcoscaceres]

Added link to Gecko tracking bug (https://bugzilla.mozilla.org/show_bug.cgi?id=1473081).

[rsolomakhin]

[marcoscaceres]

YAY!!! WELCOME BACKK!!!!

[rsolomakhin]

THANKS!

[stpeter]

Hey @rsolomakhin see email from Ian just now, too. ;-)

[rsolomakhin]

Just missed the email and the meeting, sorry! I will join the next one.

[marcoscaceres]

@rsolomakhin, when you get to it, could you drop in a tracking bug for Blink? Same for any other bugs.

[rsolomakhin]

@marcoscaceres, done. What's the meaning of the checkbox?

[marcoscaceres]

What's the meaning of the checkbox?

Not much. It’s satisfying to click tho.

[marcoscaceres]

As this depends on payment method, I'll test this as part of Basic Card: w3c/payment-method-basic-card#58