Refactor overall test suite, use replaceApp in HistoryListTest

chrome/browser/resources/md_history/app.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.
 
 cr.define('md_history', function() {
   var lazyLoadPromise = null;
   function ensureLazyLoaded() {
     if (!lazyLoadPromise) {
       lazyLoadPromise = new Promise(function(resolve, reject) {
         Polymer.Base.importHref(
@@ skipping 89 matching lines @@
     'cr-toolbar-menu-promo-shown': 'onCrToolbarMenuPromoShown_',
     'cr-toolbar-menu-tap': 'onCrToolbarMenuTap_',
     'delete-selected': 'deleteSelected',
     'history-checkbox-select': 'checkboxSelected',
     'history-close-drawer': 'closeDrawer_',
     'history-view-changed': 'historyViewChanged_',
     'opened-changed': 'onOpenedChanged_',
     'unselect-all': 'unselectAll',
   },
 
+  /** @private {?function(!Event)} */
+  onCanExecuteListener_: null,
+
+  /** @private {?function(!Event)} */
+  onCommandListener_: null,
+
   /** @override */
-  ready: function() {
+  attached: function() {
     this.grouped_ = loadTimeData.getBoolean('groupByDomain');
 
     cr.ui.decorate('command', cr.ui.Command);
-    document.addEventListener('canExecute', this.onCanExecute_.bind(this));
-    document.addEventListener('command', this.onCommand_.bind(this));
+    this.onCanExecuteListener_ = this.onCanExecute_.bind(this);

[Dan Beam, 2016/11/03 18:07:51]

nit: boundOnCanExecute_ seems to be the typical polymer way (except for, you
know, the _ at the end like the JS style guide likes)

[tsergeant, 2016/11/03 22:34:32]

Done.

+    this.onCommandListener_ = this.onCommand_.bind(this);
+
+    document.addEventListener('canExecute', this.onCanExecuteListener_);
+    document.addEventListener('command', this.onCommandListener_);
+  },
+
+  /** @override */
+  detached: function() {
+    document.removeEventListener('canExecute', this.onCanExecuteListener_);
+    document.removeEventListener('command', this.onCommandListener_);
   },
 
   onFirstRender: function() {
     setTimeout(function() {
       chrome.send(
           'metricsHandler:recordTime',
           ['History.ResultsRenderedTime', window.performance.now()]);
     });
 
     // Focus the search field on load. Done here to ensure the history page
@@ skipping 249 matching lines @@
             break;
         }
         break;
     }
 
     md_history.BrowserService.getInstance().recordHistogram(
       'History.HistoryPageView', histogramValue, HistoryPageViewHistogram.END
     );
   },
 });