Fine tuned availability of hotword plugin.

chrome/browser/resources/app_list/speech_manager.js

 // Copyright 2013 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 The class to Manage both offline / online speech recognition.
  */
 
 <include src="plugin_manager.js"/>
 <include src="audio_manager.js"/>
@@ skipping 109 matching lines @@
    * Called when the speech recognition has ended.
    */
   SpeechManager.prototype.onSpeechRecognitionEnded = function() {
     // Restarts the hotword recognition.
     if (this.state != SpeechState.STOPPING && this.pluginManager_) {
       this.pluginManager_.startRecognizer();
       this.audioManager_.start();
       this.setState_(SpeechState.HOTWORD_RECOGNIZING);
     } else {
       this.audioManager_.stop();
+      this.setState_(SpeechState.READY);
     }
-    chrome.send('setSpeechRecognitionState', ['off']);
   };
 
   /**
    * Called when a speech has started.
    */
   SpeechManager.prototype.onSpeechStarted = function() {
     if (this.state == SpeechState.RECOGNIZING)
       this.setState_(SpeechState.IN_SPEECH);
   };
 
   /**
    * Called when a speech has ended.
    */
   SpeechManager.prototype.onSpeechEnded = function() {
     if (this.state == SpeechState.IN_SPEECH)
       this.setState_(SpeechState.RECOGNIZING);
   };
 
   /**
    * Called when an error happened during the speech recognition.
    *
    * @param {SpeechRecognitionError} e The error object.
    */
   SpeechManager.prototype.onSpeechRecognitionError = function(e) {
     if (this.state != SpeechState.STOPPING)
       this.setState_(SpeechState.READY);
   };
 
   /**
-   * Initialize the hotword plugin manager, or do nothing if already
-   * initialization is on.
+   * Changes the availability of the hotword plugin.
+   *
+   * @param {boolean} enabled Whether enabled or not.
    */
-  SpeechManager.prototype.maybeInitializePlugin = function() {
-    if ($('recognizer'))
-      return;
+  SpeechManager.prototype.setHotwordEnabled = function(enabled) {
+    var recognizer = $('recognizer');
+    if (enabled) {
+      if (recognizer)
+        return;
 
-    var pluginManager = new speech.PluginManager(
-        this.onHotwordRecognizerReady_.bind(this),
-        this.onHotwordRecognized_.bind(this));
-    pluginManager.scheduleInitialize(
-        this.audioManager_.getSampleRate(),
-        'chrome://app-list/okgoogle_hotword.config');
+      var pluginManager = new speech.PluginManager(
+          this.onHotwordRecognizerReady_.bind(this),
+          this.onHotwordRecognized_.bind(this));
+      pluginManager.scheduleInitialize(
+          this.audioManager_.getSampleRate(),
+          'chrome://app-list/okgoogle_hotword.config');
+    } else {
+      if (!recognizer)
+        return;
+      document.body.removeChild(recognizer);
+      this.pluginManager_ = null;
+      if (this.state == SpeechState.HOTWORD_RECOGNIZING)
+        this.setState(SpeechState.READY);
+    }
   };
 
   /**
    * Called when the app-list bubble is shown.
    */
   SpeechManager.prototype.onShown = function() {
     this.shown_ = true;
     if (!this.pluginManager_)
       return;
 
@@ skipping 40 matching lines @@
       if (this.audioManager_.state == speech.AudioState.STOPPED)
         this.audioManager_.start();
       this.speechRecognitionManager_.start();
     }
   };
 
   return {
     SpeechManager: SpeechManager
   };
 });