Compose credit element

[michelleb-stripe]

Summary

This is the compose credit element added into PaymentSheet.

Just FYI, RUN-MOBILESDK 738 is dependent on this - Save for future use checkbox updates

In future reviews:

• trailing icon - future review - michelleb
• accessibility reading of expiration date 2/12 is read as "two hundred twelve"
• card metadata service (required before merging to master) -- should remove the ability to add more than the allowed numbers to the credit card element
• Save for future use checkbox text doesn't show up.
• Passing unit tests - michelleb
• On master the card brand doesn't populate until the last zero of 6205 50 is entered. Not sure what exactly is causing that different behavior
• The CVV icon in michelleb/credit-card-compose is not showing up, but the placeholder text does change.
• Next field from the card number appears to be the CVV instead of the date
• Only the card number shows a red line under the text when it loses focus, in dark mode, but all fields have the line under in light mode. It should be that the CVC and expiration text have a red line when the field is in error.
• If only a CVC is entered the error message shows that the card number is invalid. It should be blank, but not an error.
• Final testing

Testing

• Added tests
• Modified tests
• Manually verified

Screenshots

Before	After
before screenshot	after screenshot