Example Payment/Stripe Uncaught ReferenceError

[aaronjudd]

In checkout, the example payment causes an Uncaught ReferenceError when submitted with invalid fields.

Expected behavior

In checkout, the example payment should validate and handle the error event, letting the user update invalid fields.

Actual Behavior

example.js:95 Uncaught ReferenceError: submitting is not defined

After this the inputs are disabled as well and the user cannot update invalid inputs.

Steps to Reproduce the Behavior

Checkout and submit an example payment without required fields.

[brent-hoover]

This is also happening with Stripe as well

[brent-hoover]

Closed via #1461