Don't try to remove extension-defined content settings when extensions are disabled.

chrome/browser/profiles/off_the_record_profile_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/profiles/off_the_record_profile_impl.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/file_path.h"
@@ skipping 121 matching lines @@
 
   BrowserList::RemoveObserver(this);
 
   if (host_content_settings_map_)
     host_content_settings_map_->ShutdownOnUIThread();
 
   if (pref_proxy_config_tracker_.get())
     pref_proxy_config_tracker_->DetachFromPrefService();
 
   ExtensionService* extension_service = GetExtensionService();
-  if (extension_service) {
+  if (extension_service && extension_service->extensions_enabled()) {
     ExtensionPrefs* extension_prefs = extension_service->extension_prefs();
     extension_prefs->ClearIncognitoSessionOnlyContentSettings();
   }
 
   // Clears any data the network stack contains that may be related to the
   // OTR session.
   g_browser_process->io_thread()->ChangedToOnTheRecord();
 }
 
 void OffTheRecordProfileImpl::InitHostZoomMap() {
@@ skipping 383 matching lines @@
   OffTheRecordProfileImpl* profile = NULL;
 #if defined(OS_CHROMEOS)
   if (Profile::IsGuestSession())
     profile = new GuestSessionProfile(this);
 #endif
   if (!profile)
     profile = new OffTheRecordProfileImpl(this);
   profile->Init();
   return profile;
 }