Optimization: not sending answer server requests for voice queries.

ui/app_list/app_list_model.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 "ui/app_list/app_list_model.h"
 
 #include <string>
 #include <utility>
 
 #include "ui/app_list/app_list_folder_item.h"
@@ skipping 338 matching lines @@
 
   --custom_launcher_page_subpage_depth_;
   return true;
 }
 
 void AppListModel::ClearCustomLauncherPageSubpages() {
   custom_launcher_page_subpage_depth_ = 0;
 }
 
 void AppListModel::SetSearchEngineIsGoogle(bool is_google) {
+  if (search_engine_is_google_ == is_google)
+    return;
+
   search_engine_is_google_ = is_google;
   for (auto& observer : observers_)
     observer.OnSearchEngineIsGoogleChanged(is_google);
 }
 
 void AppListModel::SetSearchAnswerAvailable(bool has_answer) {
   for (auto& observer : observers_)
     observer.OnSearchAnswerAvailableChanged(has_answer);
 }
 
@@ skipping 76 matching lines @@
       folder->item_list()->RemoveItem(item->id());
   result->set_folder_id("");
   if (folder->item_list()->item_count() == 0) {
     DVLOG(2) << "Deleting empty folder: " << folder->ToDebugString();
     DeleteItem(folder_id);
   }
   return result;
 }
 
 }  // namespace app_list