[Payment Request] Displays accepted card types (credit, debit, etc) in iOS

ios/chrome/browser/ui/payments/payment_method_selection_mediator.mm

 // Copyright 2017 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 <vector>
 
 #import "ios/chrome/browser/ui/payments/payment_method_selection_mediator.h"
 
+#include "base/strings/string16.h"
 #include "base/strings/sys_string_conversions.h"
 #include "components/autofill/core/browser/autofill_data_util.h"
 #include "components/autofill/core/browser/autofill_profile.h"
 #include "components/autofill/core/browser/credit_card.h"
 #include "components/autofill/core/browser/personal_data_manager.h"
+#include "components/payments/core/strings_util.h"
 #include "components/strings/grit/components_strings.h"
 #include "ios/chrome/browser/payments/payment_request.h"
 #include "ios/chrome/browser/payments/payment_request_util.h"
 #import "ios/chrome/browser/ui/payments/cells/payment_method_item.h"
 #import "ios/chrome/browser/ui/payments/cells/payments_text_item.h"
 #include "ios/chrome/browser/ui/uikit_ui_util.h"
 #include "ios/chrome/grit/ios_theme_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
@@ skipping 33 matching lines @@
   return self;
 }
 
 #pragma mark - PaymentRequestSelectorViewControllerDataSource
 
 - (BOOL)allowsEditMode {
   return YES;
 }
 
 - (CollectionViewItem*)headerItem {
-  return nil;
+  base::string16 headerText = payments::GetCardTypesAreAcceptedText(
+      _paymentRequest->supported_card_types_set());
+  if (headerText.empty())
+    return nil;
+
+  PaymentsTextItem* headerItem = [[PaymentsTextItem alloc] init];
+  headerItem.text = base::SysUTF16ToNSString(headerText);
+  return headerItem;
 }
 
 - (NSArray<CollectionViewItem*>*)selectableItems {
   return self.items;
 }
 
 - (CollectionViewItem*)addButtonItem {
   PaymentsTextItem* addButtonItem = [[PaymentsTextItem alloc] init];
   addButtonItem.text = l10n_util::GetNSString(IDS_PAYMENTS_ADD_CARD);
   addButtonItem.image = NativeImage(IDR_IOS_PAYMENTS_ADD);
@@ skipping 36 matching lines @@
 
     item.reserveRoomForAccessoryType = YES;
     if (_paymentRequest->selected_credit_card() == paymentMethod)
       _selectedItemIndex = index;
 
     [_items addObject:item];
   }
 }
 
 @end