Disable sync for default apps

chrome/browser/extensions/external_provider_impl.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/external_provider_impl.h"
 
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
@@ skipping 387 matching lines @@
   // extension installer codeflow.
   provider_list->push_back(
       linked_ptr<ExternalProviderInterface>(
           new default_apps::Provider(
               profile,
               service,
               new ExternalPrefLoader(chrome::DIR_DEFAULT_APPS,
                                      ExternalPrefLoader::NONE),
               Extension::INTERNAL,
               Extension::INVALID,
-              Extension::FROM_WEBSTORE)));
+              Extension::FROM_WEBSTORE |
+                  Extension::WAS_INSTALLED_BY_DEFAULT)));
 #endif
 
 #if defined(OS_CHROMEOS)
   policy::BrowserPolicyConnector* connector =
       g_browser_process->browser_policy_connector();
   if (is_chromeos_demo_session && connector->GetAppPackUpdater()) {
     provider_list->push_back(
         linked_ptr<ExternalProviderInterface>(
           new ExternalProviderImpl(
               service,
               connector->GetAppPackUpdater()->CreateExternalLoader(),
               Extension::EXTERNAL_PREF,
               Extension::INVALID,
               Extension::NO_FLAGS)));
   }
 #endif
 }
 
 }  // namespace extensions