MAGETWO-39280: Set Total amount in checkout flow order

- changed the order of setTotals before we set service.setSelectedPaymentData and service.setSelectedPaymentInfo so subscribed observers would have the accurate totals

app/code/Magento/Checkout/view/frontend/web/js/action/select-payment-method.js

@@ -80,9 +80,10 @@ define(
                         });
                         if (proceed) {
                             quote.setPaymentMethod(methodData.method);
+                            //set the totals before setting PaymentData
+                            quote.setTotals(response);
                             service.setSelectedPaymentData(methodData);
                             service.setSelectedPaymentInfo(methodInfo);
-                            quote.setTotals(response);
                             navigator.setCurrent('paymentMethod').goNext();
                         }
                     }