Use the new hotword extension in the launcher when it is enabled.

chrome/browser/ui/app_list/app_list_view_delegate.cc

 // 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 "chrome/browser/ui/app_list/app_list_view_delegate.h"
 
 #include <vector>
 
 #include "apps/custom_launcher_page_contents.h"
 #include "base/callback.h"
@@ skipping 465 matching lines @@
   }
 }
 
 void AppListViewDelegate::OnSpeechSoundLevelChanged(int16 level) {
   speech_ui_->UpdateSoundLevel(level);
 }
 
 void AppListViewDelegate::OnSpeechRecognitionStateChanged(
     app_list::SpeechRecognitionState new_state) {
   speech_ui_->SetSpeechRecognitionState(new_state);
+
+  app_list::StartPageService* service =
+      app_list::StartPageService::Get(profile_);
+  // With the new hotword extension, we need to re-request hotwording after
+  // speech recognition has stopped.
+  if (new_state == app_list::SPEECH_RECOGNITION_READY &&
+      HotwordService::IsExperimentalHotwordingEnabled() &&
+      service && service->HotwordEnabled()) {
+    HotwordService* hotword_service =
+        HotwordServiceFactory::GetForProfile(profile_);
+    if (hotword_service) {
+      hotword_service->RequestHotwordSession(this);
+    }
+  }
 }
 
 void AppListViewDelegate::OnProfileAdded(const base::FilePath& profile_path) {
   OnProfileChanged();
 }
 
 void AppListViewDelegate::OnProfileWasRemoved(
     const base::FilePath& profile_path, const base::string16& profile_name) {
   OnProfileChanged();
 }
@@ skipping 87 matching lines @@
 
 void AppListViewDelegate::AddObserver(
     app_list::AppListViewDelegateObserver* observer) {
   observers_.AddObserver(observer);
 }
 
 void AppListViewDelegate::RemoveObserver(
     app_list::AppListViewDelegateObserver* observer) {
   observers_.RemoveObserver(observer);
 }