Improve UI for unpacked extensions failing to load

chrome/browser/resources/extensions/extensions.js

Index: chrome/browser/resources/extensions/extensions.js
diff --git a/chrome/browser/resources/extensions/extensions.js b/chrome/browser/resources/extensions/extensions.js
index 640c5aa92bcd5725e1d0fb798e7c504f9607ab6e..54a726f7f295e5eb7d1358d0dd4c77bd5dc8fb34 100644
--- a/chrome/browser/resources/extensions/extensions.js
+++ b/chrome/browser/resources/extensions/extensions.js
@@ -3,11 +3,13 @@
 // found in the LICENSE file.
 
 <include src="../uber/uber_utils.js"></include>
+<include src="extension_code.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>
@@ -101,14 +103,17 @@ cr.define('extensions', function() {
       // 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',
@@ -169,15 +174,6 @@ cr.define('extensions', function() {
     },
 
     /**
-     * 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