ntp: make the app promo button use LaunchApp instead of being a dumb <a> link

chrome/browser/resources/ntp4/apps_page.js

 // Copyright (c) 2011 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('ntp4', function() {
   'use strict';
 
   var localStrings = new LocalStrings;
 
   var APP_LAUNCH = {
@@ skipping 352 matching lines @@
      */
     createAppsPromoExtras_: function() {
       this.classList.add('webstore');
 
       this.appsPromoExtras_ = $('apps-promo-extras-template').cloneNode(true);
       this.appsPromoExtras_.id = '';
       this.appsPromoHeading_ =
           this.appsPromoExtras_.querySelector('.apps-promo-heading');
       this.appsPromoLink_ =
           this.appsPromoExtras_.querySelector('.apps-promo-link');
+      this.appsPromoLink_.addEventListener('click', this.onClick_.bind(this));
 
       this.appsPromoLogo_ = this.ownerDocument.createElement('img');
       this.appsPromoLogo_.className = 'apps-promo-logo';
       this.appImgContainer_.appendChild(this.appsPromoLogo_);
 
       this.appendChild(this.appsPromoExtras_);
       this.appsPromoExtras_.hidden = false;
     },
 
     /**
@@ skipping 409 matching lines @@
     appNotificationChanged: appNotificationChanged,
     AppsPage: AppsPage,
     launchAppAfterEnable: launchAppAfterEnable,
   };
 });
 
 // TODO(estade): update the content handlers to use ntp namespace instead of
 // making these global.
 var appNotificationChanged = ntp4.appNotificationChanged;
 var launchAppAfterEnable = ntp4.launchAppAfterEnable;