WebUI: Move test_browser_proxy.js one level up.

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

 // 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.
 
 /**
  * @constructor
  * @implements {settings.ChromeCleanupProxy}
- * @extends {settings.TestBrowserProxy}
+ * @extends {TestBrowserProxy}
  */
 var TestChromeCleanupProxy = function() {
-  settings.TestBrowserProxy.call(this, [
+  TestBrowserProxy.call(this, [
     'dismissCleanupPage',
     'getChromeCleanupVisibility',
     'registerChromeCleanupObserver',
     'restartComputer',
     'startCleanup',
   ]);
 };
 
 TestChromeCleanupProxy.prototype = {
-  __proto__: settings.TestBrowserProxy.prototype,
+  __proto__: TestBrowserProxy.prototype,
 
   /** @override */
   dismissCleanupPage: function() {
     this.methodCalled('dismissCleanupPage');
   },
 
     /** @override */
   getChromeCleanupVisibility: function() {
     this.methodCalled('getChromeCleanupVisibility');
   },
@@ skipping 87 matching lines @@
         'chrome-cleanup-on-idle',
         settings.ChromeCleanupIdleReason.CLEANING_SUCCEEDED);
     Polymer.dom.flush();
 
     var actionButton = chromeCleanupPage.$$('#action-button');
     assertTrue(!!actionButton);
     MockInteractions.tap(actionButton);
     return ChromeCleanupProxy.whenCalled('dismissCleanupPage');
   });
 });