Update references to the extension messaging APIs to point to the "runtime"

chrome/common/extensions/docs/examples/extensions/plugin_settings/js/plugin_settings.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.
 
 /**
  * @fileoverview Defines a class that provides some convenient wrapper methods
  * around the Chrome contentSettings extension API.
  */
 
 cr.define('pluginSettings', function() {
@@ skipping 33 matching lines @@
           {}, this.didClearRules_.bind(this, callback));
     },
 
     /**
      * Recreates all content settings from local storage.
      * @param {function()} callback Called when the content settings have been
      *     recreated, or on error.
      * @private
      */
     didClearRules_: function(callback) {
-      if (chrome.extension.lastError) {
+      if (chrome.runtime.lastError) {
         console.error('Error clearing rules');
         callback();
         return;
       }
       var length = window.localStorage.length;
       if (length == 0) {
         cr.dispatchSimpleEvent(settings, 'change');
         callback();
         return;
       }
@@ skipping 23 matching lines @@
      * @param {string} key The local storage key under which the content
      *     setting was stored.
      * @param {string} value The content setting value in local storage.
      * @param {{value:number}} counter Contains the number of callbacks still
      *     outstanding.
      * @param {function()} callback Called when the content settings have been
      *     recreated, or on error.
      * @private
      */
     didSetContentSetting_: function(plugin, pattern, key, counter, callback) {
-      if (chrome.extension.lastError) {
+      if (chrome.runtime.lastError) {
         console.error(
             'Error restoring [' + key + ': ' + value + ']: ' +
-                chrome.extension.lastError.message);
+                chrome.runtime.lastError.message);
         window.localStorage.removeItem(key);
       }
       counter.value--;
       if (counter.value == 0) {
         cr.dispatchSimpleEvent(this, 'change');
         callback();
       }
     },
 
     /**
      * Creates a content setting rule and calls the passed in callback with the
      * result.
      * @param {string} pattern The content setting pattern for the rule.
      * @param {string} setting The setting for the rule.
      * @param {function(?string)} callback Called when the content settings
      *     have been updated, or on error.
      */
     set: function(pattern, setting, callback) {
       var plugin = this.plugin_;
       var settings = this;
       chrome.contentSettings.plugins.set({
         'primaryPattern': pattern,
         'resourceIdentifier': { 'id': plugin },
         'setting': setting,
       }, function() {
-        if (chrome.extension.lastError) {
-          callback(chrome.extension.lastError.message);
+        if (chrome.runtime.lastError) {
+          callback(chrome.runtime.lastError.message);
         } else {
           window.localStorage.setItem(JSON.stringify([plugin, pattern]),
                                       setting);
           cr.dispatchSimpleEvent(settings, 'change');
           callback();
         }
       });
     },
 
     /**
@@ skipping 72 matching lines @@
         }
       }
       return rules;
     }
   };
 
   return {
     Settings: Settings,
   }
 });