Fix the System Profile to not load extensions. It could otherwise be forced to by GPO.

chrome/browser/extensions/tab_helper.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/tab_helper.h"
 
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chrome_notification_types.h"
@@ skipping 126 matching lines @@
 bool TabHelper::CanCreateApplicationShortcuts() const {
 #if defined(OS_MACOSX)
   return false;
 #else
   return web_app::IsValidUrl(web_contents()->GetURL());
 #endif
 }
 
 bool TabHelper::CanCreateBookmarkApp() const {
   return !profile_->IsGuestSession() &&
+         !profile_->IsSystemProfile() &&
          IsValidBookmarkAppUrl(web_contents()->GetURL());
 }
 
 void TabHelper::AddScriptExecutionObserver(ScriptExecutionObserver* observer) {
   script_execution_observers_.AddObserver(observer);
 }
 
 void TabHelper::RemoveScriptExecutionObserver(
     ScriptExecutionObserver* observer) {
   script_execution_observers_.RemoveObserver(observer);
@@ skipping 420 matching lines @@
   }
 }
 
 void TabHelper::SetTabId(RenderViewHost* render_view_host) {
   render_view_host->Send(
       new ExtensionMsg_SetTabId(render_view_host->GetRoutingID(),
                                 SessionTabHelper::IdForTab(web_contents())));
 }
 
 }  // namespace extensions