To repro:

Have a valid address and a card with the billing address set to the profile.

1- Go to https://googlechrome.github.io/samples/paymentrequest/free-shipping/
2- Complete a payment
3- Go in the Autofill settings and delete the address
4- Press pay again

The address is not present in shipping section but is still present and assigned as being the billing address for the card.

Note that this doesn't happen on rsolomakhin.github.io. I think it's because on that site you need to reload the page to do another Payment Request.

So the bug might be related to the lifetime of the PaymentRequest obj?