Fix a crash on closing cookies and site info bubble.

chrome/browser/ui/aura/chrome_browser_main_extra_parts_aura.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/ui/aura/chrome_browser_main_extra_parts_aura.h"
 
 #include "base/command_line.h"
 #include "base/run_loop.h"
 #include "chrome/browser/chrome_browser_main.h"
 #include "chrome/browser/ui/aura/active_desktop_monitor.h"
@@ skipping 26 matching lines @@
 #endif  // defined(USE_ASH)
 
 #if !defined(OS_CHROMEOS)
 #include "ui/views/widget/desktop_aura/desktop_screen.h"
 #endif
 
 namespace {
 
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
 ui::NativeTheme* GetNativeThemeForWindow(aura::Window* window) {
+  if (!window)
+    return NULL;
+
   Profile* profile = NULL;
   if (window->type() == ui::wm::WINDOW_TYPE_NORMAL ||
       window->type() == ui::wm::WINDOW_TYPE_POPUP) {
     profile = reinterpret_cast<Profile*>(
         window->GetNativeWindowProperty(Profile::kProfileKey));
   }
 
   if (profile && !profile->GetPrefs()->GetBoolean(prefs::kUsesSystemTheme))
     return ui::NativeThemeAura::instance();
 
@@ skipping 92 matching lines @@
                            chrome::MESSAGE_BOX_TYPE_WARNING);
 
     // Avoids gpu_process_transport_factory.cc(153)] Check failed:
     // per_compositor_data_.empty() when quit is chosen.
     base::RunLoop().RunUntilIdle();
 
     exit(EXIT_FAILURE);
   }
 }
 #endif