Cancels payment request when Settings is tapped, and opens the Autofill settings page.

ios/chrome/browser/payments/payment_request_view_controller.mm

 // 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.
 
 #import "ios/chrome/browser/payments/payment_request_view_controller.h"
 
 #include "base/mac/foundation_util.h"
 
 #include "base/strings/stringprintf.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 483 matching lines @@
   DCHECK(profile);
   item.name = GetNameLabelFromAutofillProfile(*profile);
   item.phoneNumber = GetPhoneNumberLabelFromAutofillProfile(*profile);
   item.email = GetEmailLabelFromAutofillProfile(*profile);
 }
 
 #pragma mark - CollectionViewFooterLinkDelegate
 
 - (void)cell:(CollectionViewFooterCell*)cell didTapLinkURL:(GURL)url {
   DCHECK_EQ(url, GURL(kSettingsURL)) << "Unknown URL tapped";
-  NOTIMPLEMENTED();  // TODO(macourteau): take the user to the right place.
+  [_delegate paymentRequestViewControllerDidSelectSettings:self];
 }
 
 #pragma mark UICollectionViewDataSource
 
 - (UICollectionViewCell*)collectionView:(UICollectionView*)collectionView
                  cellForItemAtIndexPath:(nonnull NSIndexPath*)indexPath {
   UICollectionViewCell* cell =
       [super collectionView:collectionView cellForItemAtIndexPath:indexPath];
 
   NSInteger itemType =
@@ skipping 103 matching lines @@
 
 - (BOOL)collectionView:(UICollectionView*)collectionView
     shouldHideItemBackgroundAtIndexPath:(NSIndexPath*)indexPath {
   // No background on the footer text item.
   NSInteger sectionIdentifier =
       [self.collectionViewModel sectionIdentifierForSection:indexPath.section];
   return sectionIdentifier == SectionIdentifierFooter ? YES : NO;
 }
 
 @end