Add option in about:flags to disable Quickoffice component extension

chrome/browser/extensions/component_loader.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/extensions/component_loader.h"
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/json/json_string_value_serializer.h"
 #include "base/path_service.h"
@@ skipping 424 matching lines @@
         base::FilePath(FILE_PATH_LITERAL("settings_app")));
 #endif
   }
 
 #if defined(OS_CHROMEOS)
   if (!skip_session_components) {
     Add(IDR_WALLPAPERMANAGER_MANIFEST,
         base::FilePath(FILE_PATH_LITERAL("chromeos/wallpaper_manager")));
 
 #if defined(GOOGLE_CHROME_BUILD)
-    if (browser_defaults::enable_component_quick_office) {
+    if (!command_line->HasSwitch(
+            chromeos::switches::kDisableQuickofficeComponentApp)) {
       std::string id = Add(IDR_QUICK_OFFICE_MANIFEST, base::FilePath(
           FILE_PATH_LITERAL("/usr/share/chromeos-assets/quick_office")));
       if (command_line->HasSwitch(chromeos::switches::kGuestSession)) {
         // TODO(dpolukhin): Hack to enable HTML5 temporary file system for
         // Quickoffice. It doesn't work without temporary file system access.
         Profile* profile = ProfileManager::GetDefaultProfileOrOffTheRecord();
         ExtensionService* service =
             extensions::ExtensionSystem::Get(profile)->extension_service();
         GURL site = service->GetSiteForExtensionId(id);
         fileapi::FileSystemContext* context =
@@ skipping 48 matching lines @@
 void ComponentLoader::RegisterUserPrefs(PrefRegistrySyncable* registry) {
   registry->RegisterStringPref(prefs::kEnterpriseWebStoreURL,
                                std::string() /* default_value */,
                                PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterStringPref(prefs::kEnterpriseWebStoreName,
                                std::string() /* default_value */,
                                PrefRegistrySyncable::UNSYNCABLE_PREF);
 }
 
 }  // namespace extensions