[Payments] Use formatter currency code on desktop

components/payments/payment_details_validation.cc

Index: components/payments/payment_details_validation.cc
diff --git a/components/payments/payment_details_validation.cc b/components/payments/payment_details_validation.cc
index a01303e904cea9bb89f2005d2865de3bf7a3ed24..81c42cdbb4924298c0e2f32f831986b48a999677 100644
--- a/components/payments/payment_details_validation.cc
+++ b/components/payments/payment_details_validation.cc
@@ -44,15 +44,15 @@ bool validateShippingOptionOrPaymentItem(
     return false;
   }
 
-  if (item->amount->currencySystem.has_value() &&
-      item->amount->currencySystem.value().empty()) {
+  if (item->amount->currency_system.has_value() &&
+      item->amount->currency_system.value().empty()) {
     *error_message = "Currency system can't be empty";
     return false;
   }
 
   if (!payments::PaymentsValidators::isValidCurrencyCodeFormat(
-          item->amount->currency, item->amount->currencySystem.has_value()
-                                      ? item->amount->currencySystem.value()
+          item->amount->currency, item->amount->currency_system.has_value()
+                                      ? item->amount->currency_system.value()
                                       : "",
           error_message)) {
     return false;