[Web Payments] Implement the credit card selection UI functionality.

chrome/browser/ui/views/payments/payment_request_dialog_view_ids.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_VIEWS_PAYMENTS_PAYMENT_REQUEST_DIALOG_VIEW_IDS_H_
 #define CHROME_BROWSER_UI_VIEWS_PAYMENTS_PAYMENT_REQUEST_DIALOG_VIEW_IDS_H_
 
 #include "components/autofill/core/browser/field_types.h"
 
 // This defines an enumeration of IDs that can uniquely identify a view within
@@ skipping 11 matching lines @@
   PAYMENT_SHEET_SUMMARY_SECTION,
   PAYMENT_METHOD_ADD_CARD_BUTTON,
   EDITOR_SAVE_BUTTON,
 
   // The following are StyledLabel objects.
   ORDER_SUMMARY_TOTAL_AMOUNT_LABEL,
   ORDER_SUMMARY_LINE_ITEM_1,
   ORDER_SUMMARY_LINE_ITEM_2,
   ORDER_SUMMARY_LINE_ITEM_3,
 
+  // The following are views contained within the Payment Method Sheet.
+  PAYMENT_METHOD_SHEET_LIST_VIEW,
+  PAYMENT_METHOD_ITEM_CHECKMARK_VIEW,
+
   // Used to label the error labels with an offset, which gets added to
   // the Autofill type value they represent (for tests).
   ERROR_LABEL_OFFSET,
 };
 
 }  // namespace payments
 
 #endif  // CHROME_BROWSER_UI_VIEWS_PAYMENTS_PAYMENT_REQUEST_DIALOG_VIEW_IDS_H_