Leaving payment page with single use coupon code makes it invalid

Steps to reproduce:
1. Add items to cart and proceed to cart page
2. Add coupon with has usage per customer limit set to 1
3. Proceed to payment method selection page
4. Come back to cart page and change it (or come back to shipping method and change it)

Observe that cart is recalculated and coupon is no longer applied.

Expectation is that all valid coupons still remain valid and applied to current cart