enable modifiers for native apps

chrome/test/data/payments/modifier.js

-/*

[please use gerrit instead, 2017/05/22 13:17:10]

Let's not delete existing test cases.

[wuandy1, 2017/05/23 15:46:58]

Done.

- * 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.
- */
-
-/**
- * Invokes the PaymentRequest with a modifier that contains the bare mininum of
- * required fields.
- */
-function buy() { // eslint-disable-line no-unused-vars
-  try {
-    new PaymentRequest(
-        [{
-          supportedMethods: ['foo'],
-        }], {
-          total: {
-            label: 'Total',
-            amount: {
-              currency: 'USD',
-              value: '5.00',
-            },
-          },
-          modifiers: [{
-            supportedMethods: ['foo'],
-          }],
-        })
-      .show()
-      .then(function(response) {
-        response.complete()
-          .then(function() {
-            print(complete);
-          })
-          .catch(function(error) {
-            print(error);
-          });
-      })
-      .catch(function(error) {
-        print(error);
-      });
-  } catch (error) {
-    print(error.message);
-  }
-}