Improve UI for unpacked extensions failing to load

chrome/browser/resources/extensions/extensions.js

 // Copyright (c) 2012 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.
 
 <include src="../uber/uber_utils.js"></include>
+
+// Include this before extensions modules.
+<include src="extension_util.js"></include>
+
 <include src="extension_commands_overlay.js"></include>
 <include src="extension_focus_manager.js"></include>
 <include src="extension_list.js"></include>
 <include src="pack_extension_overlay.js"></include>
 <include src="extension_error_overlay.js"></include>
+<include src="extension_loader.js"></include>
 
 <if expr="chromeos">
 <include src="chromeos/kiosk_apps.js"></include>
 </if>
 
 // Used for observing function of the backend datasource for this page by
 // tests.
 var webuiResponded = false;
 
 cr.define('extensions', function() {
@@ skipping 73 matching lines @@
       measureCheckboxStrings();
 
       // Set the title.
       var title = loadTimeData.getString('extensionSettings');
       uber.invokeMethodOnParent('setTitle', {title: title});
 
       // This will request the data to show on the page and will get a response
       // back in returnExtensionsData.
       chrome.send('extensionSettingsRequestExtensionsData');
 
+      var extensionLoader = extensions.ExtensionLoader.getInstance();
+
       $('toggle-dev-on').addEventListener('change',
           this.handleToggleDevMode_.bind(this));
       $('dev-controls').addEventListener('webkitTransitionEnd',
           this.handleDevControlsTransitionEnd_.bind(this));
 
       // Set up the three dev mode buttons (load unpacked, pack and update).
-      $('load-unpacked').addEventListener('click',
-          this.handleLoadUnpackedExtension_.bind(this));
+      $('load-unpacked').addEventListener('click', function(e) {
+          extensionLoader.loadUnpacked();
+      });
       $('pack-extension').addEventListener('click',
           this.handlePackExtension_.bind(this));
       $('update-extensions-now').addEventListener('click',
           this.handleUpdateExtensionNow_.bind(this));
 
       // Set up the close dialog for the apps developer tools promo.
       $('apps-developer-tools-promo').querySelector('.close-button').
           addEventListener('click', function(e) {
         $('extension-settings').classList.remove('adt-promo');
         chrome.send('extensionSettingsDismissADTPromo');
@@ skipping 40 matching lines @@
         // Skip starting slash and remove trailing slash (if any).
         var overlayName = path.slice(1).replace(/\/$/, '');
         if (overlayName == 'configureCommands')
           this.showExtensionCommandsConfigUi_();
       }
 
       preventDefaultOnPoundLinkClicks();  // From webui/js/util.js.
     },
 
     /**
-     * Handles the Load Unpacked Extension button.
-     * @param {Event} e Change event.
-     * @private
-     */
-    handleLoadUnpackedExtension_: function(e) {
-      chrome.send('extensionSettingsLoadUnpackedExtension');
-    },
-
-    /**
      * Handles the Pack Extension button.
      * @param {Event} e Change event.
      * @private
      */
     handlePackExtension_: function(e) {
       ExtensionSettings.showOverlay($('pack-extension-overlay'));
       chrome.send('metricsHandler:recordAction', ['Options_PackExtension']);
     },
 
     /**
@@ skipping 217 matching lines @@
 
   // Export
   return {
     ExtensionSettings: ExtensionSettings
   };
 });
 
 window.addEventListener('load', function(e) {
   extensions.ExtensionSettings.getInstance().initialize();
 });