MD Settings: Fix case where 'REMOVE ALL SHOWN' button is erroneously shown.

chrome/test/data/webui/settings/site_data_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.
 
 suite('<site-data>', function() {
   /** @type {SiteDataElement} */
   var siteData;
 
   /** @type {TestSiteSettingsPrefsBrowserProxy} */
   var testBrowserProxy;
 
   setup(function() {
     testBrowserProxy = new TestSiteSettingsPrefsBrowserProxy;
     settings.SiteSettingsPrefsBrowserProxyImpl.instance_ = testBrowserProxy;
     siteData = document.createElement('site-data');
   });
 
   test('tapping remove button (trash can) calls remove on origin', function() {
     var GOOGLE_ID = '1';
     siteData.sites = [{site: 'Google', id: GOOGLE_ID, localData: 'Cookiez!'}];
     Polymer.dom.flush();
 
     MockInteractions.tap(siteData.$$('.remove-site'));
 
     return testBrowserProxy.whenCalled('removeCookie').then(function(path) {
       assertEquals(GOOGLE_ID, path);
     });
   });
+
+  test('remove button hidden when no search results', function() {
+    siteData.sites = [
+      {site: 'Hello', id: '1', localData: 'Cookiez!'},
+      {site: 'World', id: '2', localData: 'Cookiez!'},
+    ];
+
+    Polymer.dom.flush();
+    assertEquals(
+        siteData.sites.length,
+        siteData.shadowRoot.querySelectorAll('.list-item').length);
+
+    // Expecting one result, so the button should be shown.
+    siteData.$.filter.dispatchEvent(
+        new CustomEvent('search-changed', {detail: 'Hello'}));
+    Polymer.dom.flush();
+    assertEquals(
+        1, siteData.shadowRoot.querySelectorAll('.list-item').length);
+    assertFalse(siteData.$.removeShowingSites.hidden);
+
+    // Expecting no results, so the button should be hidden.
+    siteData.$.filter.dispatchEvent(
+        new CustomEvent('search-changed', {detail: 'foo'}));
+    Polymer.dom.flush();
+    assertEquals(
+        0, siteData.shadowRoot.querySelectorAll('.list-item').length);
+    assertTrue(siteData.$.removeShowingSites.hidden);
+  });
 });