MD Downloads: fix search spinner when terms are the same

chrome/test/data/webui/md_downloads/toolbar_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.
 
 suite('toolbar tests', function() {
   /** @type {!downloads.Toolbar} */
   var toolbar;
 
   setup(function() {
+    /**
+     * @constructor
+     * @extends {downloads.ActionService}
+     */
+    function TestActionService() {
+      downloads.ActionService.call(this);
+    }
+
+    TestActionService.prototype = {
+      __proto__: downloads.ActionService.prototype,
+      loadMore: function() { /* Prevent chrome.send(). */ },
+    };
+
     toolbar = document.createElement('downloads-toolbar');
+    downloads.ActionService.instance_ = new TestActionService;
     document.body.appendChild(toolbar);
   });
 
   test('resize closes more options menu', function() {
     MockInteractions.tap(toolbar.$$('paper-icon-button'));
     assertTrue(toolbar.$.more.opened);
 
     window.dispatchEvent(new CustomEvent('resize'));
     assertFalse(toolbar.$.more.opened);
   });
+
+  test('search starts spinner', function() {
+    toolbar.$.toolbar.fire('search-changed', 'a');
+    assertTrue(toolbar.spinnerActive);
+
+    // Pretend the manager got results and set this to false.
+    toolbar.spinnerActive = false;
+
+    toolbar.$.toolbar.fire('search-changed', 'a ');  // Same term plus a space.
+    assertFalse(toolbar.spinnerActive);
+  });
 });