MD Settings: Remove unnecessary importHtml() calls in site-settings tests.

chrome/test/data/webui/settings/usb_devices_tests.js

 // 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.
 
 /** @fileoverview Suite of tests for usb_devices. */
 cr.define('usb_devices', function() {
   function registerTests() {
     suite('UsbDevices', function() {
       /**
        * A dummy usb-devices element created before each test.
@@ skipping 32 matching lines @@
             "serial-number": "device-2-sn",
             "vendor-id": 2
           },
           objectName: 'device-2',
           origin: 'device-2-origin',
           setting: 'device-2-settings',
           source: 'device-2-source'
         }
       ];
 
-      // Import necessary html before running suite.
-      suiteSetup(function() {
-        return PolymerTest.importHtml(
-           'chrome://md-settings/site_settings/usb_devices.html');
-      });
-
       setup(function() {
         browserProxy = new TestSiteSettingsPrefsBrowserProxy();
         settings.SiteSettingsPrefsBrowserProxyImpl.instance_ = browserProxy;
       });
 
       teardown(function() {
         testElement.remove();
         testElement = null;
       });
 
@@ skipping 77 matching lines @@
           return testRemovalFlow(1);
         });
       });
     });
   }
 
   return {
     registerTests: registerTests,
   };
 });