Don't start the hotword extension on Chrome startup if the user doesn't have hotwording enabled.

chrome/browser/resources/hotword/manager.js

 // Copyright 2014 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.
 
 (function() {
   'use strict';
 
   /**
    * @fileoverview This extension provides hotword triggering capabilites to
    * Chrome.
    *
    * This extension contains all the JavaScript for loading and managing the
    * hotword detector. The hotword detector and language model data will be
    * provided by a shared module loaded from the web store.
    *
    * IMPORTANT! Whenever adding new events, the extension version number MUST be
    * incremented.
    */
 
   // Hotwording state.
   var stateManager = new hotword.StateManager();
   var pageAudioManager = new hotword.PageAudioManager(stateManager);
   var alwaysOnManager = new hotword.AlwaysOnManager(stateManager);
   var launcherManager = new hotword.LauncherManager(stateManager);
   var trainingManager = new hotword.TrainingManager(stateManager);
 
-  // Detect Chrome startup and make sure we get a chance to run.
-  chrome.runtime.onStartup.addListener(function() {
-    stateManager.updateStatus();
-  });
-
   // Detect when hotword settings have changed.
   chrome.hotwordPrivate.onEnabledChanged.addListener(function() {
     stateManager.updateStatus();
   });
 
   // Detect a request to delete the speaker model.
   chrome.hotwordPrivate.onDeleteSpeakerModel.addListener(function() {
     hotword.TrainingManager.handleDeleteSpeakerModel();
   });
 
   // Detect a request for the speaker model existence.
   chrome.hotwordPrivate.onSpeakerModelExists.addListener(function() {
     hotword.TrainingManager.handleSpeakerModelExists();
   });
 
   // Detect when the shared module containing the NaCL module and language model
   // is installed.
   chrome.management.onInstalled.addListener(function(info) {
     if (info.id == hotword.constants.SHARED_MODULE_ID) {
       hotword.debug('Shared module installed, reloading extension.');
       chrome.runtime.reload();
     }
   });
 }());