[DRAFT] [Connect] Using FinancialConnections SDK in Connect

[mludowise-stripe]

Summary

Enables using the mobile native FinancialConnections SDK from Connect web components to retrieve the user's bank token.

• Adds a dependency from StripeConnect -> StripeFinancialConnections
• Adds a new JS message handler and sender to trigger the FinancialConnections flow from web and pass back the bank token:
  • openFinancialConnections message handler: Triggers the FinancialConnectionsSheet to open:
    • Param clientSecret: The Financial Connections Session client secret for the connected account
    • Param id: A unique UUID that gets passed back to the web layer on returnFromFinancialConnections
  • returnedFromFinancialConnections message sender: Returns the connected bank token to the web layer
    • Param bankToken: The bank account token of the connected account. This value will be null if the user canceled out of the flow or an error occurred
    • Param id: The id originally passed to the mobile layer from openFinancialConnections

Motivation

https://jira.corp.stripe.com/browse/MXMOBILE-2526
https://docs.google.com/document/d/1WUTvnK8kqsB00zcmUzwVC_CW5MMmXC_CDk8eQTAzaaQ

Testing

Demo video (turn on audio):
https://drive.google.com/file/d/1I7W559oCf10uVNPYvQADRukNzw3MK_zY

TODO

• Confirm JS<>Mobile messaging layer shape
• Unit test coverage for message handlers / senders

[mludowise-stripe]

Alternatively, if we don't need to return the bank token, we could send a success | cancelled | failed enum value to the web view

[github-actions]

⚠️ Public API changes detected:

StripePaymentSheet

- public var paymentMethodLayout: StripePaymentSheet.PaymentSheet.PaymentMethodLayout
- public enum PaymentMethodLayout {
- case horizontal
- case vertical
- case automatic
- public static func == (a: StripePaymentSheet.PaymentSheet.PaymentMethodLayout, b: StripePaymentSheet.PaymentSheet.PaymentMethodLayout) -> Swift.Bool
- public func hash(into hasher: inout Swift.Hasher)
- public var hashValue: Swift.Int {
- get
- }
- }

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