EarlGrey tests for Payment Request (base CL)

ios/chrome/browser/payments/payment_items_display_view_controller.mm

Index: ios/chrome/browser/payments/payment_items_display_view_controller.mm
diff --git a/ios/chrome/browser/payments/payment_items_display_view_controller.mm b/ios/chrome/browser/payments/payment_items_display_view_controller.mm
index 011993caebd39d76bffa5e4556437c379b2e3861..1a4661fc06119f8054ec23de3c9997559f5a58fa 100644
--- a/ios/chrome/browser/payments/payment_items_display_view_controller.mm
+++ b/ios/chrome/browser/payments/payment_items_display_view_controller.mm
@@ -8,6 +8,7 @@
 #include "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #include "components/autofill/core/browser/credit_card.h"
+#include "components/strings/grit/components_strings.h"
 #import "ios/chrome/browser/payments/cells/order_summary_line_item.h"
 #import "ios/chrome/browser/payments/cells/order_summary_total_item.h"
 #import "ios/chrome/browser/ui/collection_view/cells/collection_view_detail_item.h"
@@ -22,6 +23,7 @@
 
 NSString* const kPaymentItemsDisplayCollectionViewId =
     @"kPaymentItemsDisplayCollectionViewId";
+NSString* const kPaymentItemsDisplayItemId = @"kPaymentItemsDisplayItemId";
 
 namespace {
 
@@ -66,6 +68,8 @@ typedef NS_ENUM(NSInteger, ItemType) {
         [ChromeIcon templateBarButtonItemWithImage:[ChromeIcon backIcon]
                                             target:nil
                                             action:@selector(onReturn)];
+    [returnButton
+        setAccessibilityLabel:l10n_util::GetNSString(IDS_ACCNAME_BACK)];
     [self navigationItem].leftBarButtonItem = returnButton;
 
     // Set up right (pay) button.
@@ -142,6 +146,7 @@ typedef NS_ENUM(NSInteger, ItemType) {
   // Add the total entry.
   OrderSummaryTotalItem* totalItem = [[[OrderSummaryTotalItem alloc]
       initWithType:ItemTypePaymentItem] autorelease];
+  totalItem.accessibilityIdentifier = kPaymentItemsDisplayItemId;
   totalItem.text = base::SysUTF16ToNSString(_total.label);
 
   NSString* currencyCode = base::SysUTF16ToNSString(_total.amount.currency);
@@ -157,6 +162,7 @@ typedef NS_ENUM(NSInteger, ItemType) {
     web::PaymentItem paymentItem = _paymentItems[i];
     OrderSummaryLineItem* paymentItemItem = [[[OrderSummaryLineItem alloc]
         initWithType:ItemTypePaymentItem] autorelease];
+    paymentItemItem.accessibilityIdentifier = kPaymentItemsDisplayItemId;
     paymentItemItem.text = base::SysUTF16ToNSString(paymentItem.label);
 
     NSString* currencyCode =