Add paymentMethodErrors, payerErrors, to PaymentDetailsUpdate

[marcoscaceres]

• closes #766

The following tasks have been completed:

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

Implementation commitment:

• [x] Safari
• [ ] Chrome
• [x] Firefox
• [ ] Edge (public signal)

Optional, Impact on Payment Handler spec?

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Preview | Diff

[marcoscaceres]

@romandev, I saw you were helping implementing .retry() on the Chrome side. Is that correct?

[marcoscaceres]

@romandev wrote:

Yep, I'm implementing retry() feature in Chromium under @rsolomakhin's high-quality review.

Excellent to hear! What do you think of the proposed fix here? Make sense from an implementation perspective?

[marcoscaceres]

One question is whether the some error values can be updated via updateWith() on an unrelated event. For example, requestShipping and requestPayerName are all true and merchant calls updateWith() on payer detail change event as follows.

I think it's fine, tbh.

In this case, should we allow shippingAddressErrors to be updated on payer detail change event?

I think we should allow it - just to reduce our (implementation) complexity. It's not different from a developer randomly invalidating their form elements.

[marcoscaceres]

This is implemented in Firefox as part of https://bugzilla.mozilla.org/show_bug.cgi?id=1435161

[marcoscaceres]

@romandev, can I get implementation commitment from the Blink side?

[romandev]

@marcoscaceres Sure. I'm working on it.

[marcoscaceres]

@romandev awesome to hear. When you can, could you drop add a tracking bug? 🙏

[romandev]

I also filed this in Chromium :) https://bugs.chromium.org/p/chromium/issues/detail?id=884433

[marcoscaceres]

We've implemented this in Firefox. Landing this with @romandev's r+.

[aestes]

We've implemented this in WebKit: https://trac.webkit.org/r236552