[Web Payments] Add Cancel button to all sheets

chrome/browser/ui/views/payments/payment_sheet_view_controller.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 "chrome/browser/ui/views/payments/payment_sheet_view_controller.h"
 
 #include <algorithm>
 #include <memory>
 #include <utility>
 #include <vector>
@@ skipping 186 matching lines @@
       CreateSheetHeaderView(
           false,
           l10n_util::GetStringUTF16(IDS_PAYMENT_REQUEST_PAYMENT_SHEET_TITLE),
           this),
       std::move(content_view));
 }
 
 void PaymentSheetViewController::ButtonPressed(
     views::Button* sender, const ui::Event& event) {
   switch (sender->tag()) {
-    case static_cast<int>(PaymentRequestCommonTags::CLOSE_BUTTON_TAG):
-      dialog()->CloseDialog();
-      break;
-
     case static_cast<int>(
         PaymentSheetViewControllerTags::SHOW_ORDER_SUMMARY_BUTTON):
       dialog()->ShowOrderSummary();
       break;
 
     case static_cast<int>(PaymentSheetViewControllerTags::SHOW_SHIPPING_BUTTON):
       dialog()->ShowShippingListSheet();
       break;
 
     case static_cast<int>(
         PaymentSheetViewControllerTags::SHOW_PAYMENT_METHOD_BUTTON):
       dialog()->ShowPaymentMethodSheet();
       break;
 
     case static_cast<int>(
         PaymentSheetViewControllerTags::SHOW_CONTACT_INFO_BUTTON):
       // TODO(tmartino): Transition to contact info page once it exists.
       break;
 
     default:
-      NOTREACHED();
+      PaymentRequestSheetController::ButtonPressed(sender, event);
+      break;
   }
 }
 
 std::unique_ptr<views::View>
 PaymentSheetViewController::CreateOrderSummarySectionContent() {
   CurrencyFormatter* formatter = request()->GetOrCreateCurrencyFormatter(
       request()->details()->total->amount->currency,
       request()->details()->total->amount->currency_system,
       g_browser_process->GetApplicationLocale());
   base::string16 label_value = l10n_util::GetStringFUTF16(
@@ skipping 140 matching lines @@
       CreateContactInfoSectionContent(), std::unique_ptr<views::View>(nullptr),
       widest_name_column_view_width_);
   section->set_tag(static_cast<int>(
       PaymentSheetViewControllerTags::SHOW_CONTACT_INFO_BUTTON));
   section->set_id(
       static_cast<int>(DialogViewID::PAYMENT_SHEET_CONTACT_INFO_SECTION));
   return section;
 }
 
 }  // namespace payments