PaymentRequest: The currencySystem should be non-nullable.

components/payments/payment_details_validation.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/payments/payment_details_validation.h"
 
 #include <set>
 #include <vector>
 
 #include "components/payments/payment_request.mojom.h"
@@ skipping 26 matching lines @@
   if (item->amount->value.empty()) {
     *error_message = "Currency value required";
     return false;
   }
 
   if (item->amount->currency != total->amount->currency) {
     *error_message = "Currencies must all be equal";
     return false;
   }
 
-  if (item->amount->currency_system.has_value() &&
-      item->amount->currency_system.value().empty()) {
+  if (item->amount->currency_system.empty()) {
     *error_message = "Currency system can't be empty";
     return false;
   }
 
   if (!payments::PaymentsValidators::isValidCurrencyCodeFormat(
-          item->amount->currency, item->amount->currency_system.has_value()
-                                      ? item->amount->currency_system.value()
-                                      : "",
+          item->amount->currency, item->amount->currency_system,
           error_message)) {
     return false;
   }
 
   if (!payments::PaymentsValidators::isValidAmountFormat(item->amount->value,
                                                          error_message)) {
     return false;
   }
   return true;
 }
@@ skipping 109 matching lines @@
     if (!validatePaymentDetailsModifiers(details->modifiers, details->total,
                                          error_message))
       return false;
   }
   if (!PaymentsValidators::isValidErrorMsgFormat(details->error, error_message))
     return false;
   return true;
 }
 
 }  // namespace payments