Self-check - pay fines doesn't work with Stripe

Some of our libraries are now accepting online credit card payments through the My Account interface of the OPAC using Stripe. I was hoping we'd also be able to accept payments through the Self-Check interface this way, but it appears to be using different code to handle payment processing - when I try testing using the same test accounts through My Account, it gives the error:

Event: 4020:CREDIT_PROCESSOR_DECLINED_TRANSACTION -> The credit card processor has declined the transaction. undefined

Jason Boyer supplied the following feedback:

"If the selfcheck uses a separate interface it will have to be customized to make use of Stripe payment processing. The main payment form has several customizations only enabled when using Stripe because of the way payments are accepted through that service. A "regular" payment form will pass all of the parameters to an Evergreen backend which doesn't know what to do at that point. The short version of the details: the CC number and associated info aren't passed to Evergreen, only a payment token, Eg then uses that token to bill the patron instead of the CC number directly. The logic to pass the number back and forth to Stripe and generate that token isn't present in the backend (and would defeat the purpose of using Stripe, in that the Evergreen server never sees the CC number.) For the (only slightly, now) longer answer see how Open-ILS/src/templates/opac/myopac/main_payment_form.tt2 changes when ctx.use_stripe is 1."

Submitting to launchpad as a wish list request to add the Stripe (and Paypal and Authorize.net) modifications that have been made to the My Account payment process to the self-check payment process as well.

Evergreen 2.9