[ObjC ARC] Converts ios/chrome/browser/ui/settings:unit_tests to ARC.

ios/chrome/browser/payments/credit_card_edit_view_controller_unittest.mm

Index: ios/chrome/browser/payments/credit_card_edit_view_controller_unittest.mm
diff --git a/ios/chrome/browser/payments/credit_card_edit_view_controller_unittest.mm b/ios/chrome/browser/payments/credit_card_edit_view_controller_unittest.mm
index 652c4a5cd9bae3b4ec4455afcd7455139a3fc05a..3324b133bf15943b026b00460304c52586d284d9 100644
--- a/ios/chrome/browser/payments/credit_card_edit_view_controller_unittest.mm
+++ b/ios/chrome/browser/payments/credit_card_edit_view_controller_unittest.mm
@@ -59,7 +59,7 @@ NSArray<EditorField*>* editorFields() {
 class PaymentRequestCreditCardEditViewControllerTest
     : public CollectionViewControllerTest {
  protected:
-  CollectionViewController* NewController() override NS_RETURNS_RETAINED {
+  CollectionViewController* InstantiateController() override {
     payment_request_ = base::MakeUnique<PaymentRequest>(
         payment_request_test_util::CreateTestWebPaymentRequest(),
         &personal_data_manager_);