Fixes possible crash in content shell shutdown

content/shell/browser/shell_views.cc

 // Copyright 2013 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 "content/shell/browser/shell.h"
 
 #include <stddef.h>
 
 #include "base/command_line.h"
 #include "base/macros.h"
@@ skipping 331 matching lines @@
   views_delegate_ = new views::DesktopTestViewsDelegate();
 }
 
 void Shell::PlatformExit() {
 #if defined(OS_CHROMEOS)
   delete wm_test_helper_;
   wm_test_helper_ = nullptr;
 
   delete test_screen_;
   test_screen_ = nullptr;
-#elif defined(USE_AURA)
-  delete wm_state_;
-  wm_state_ = nullptr;
 #endif
   delete views_delegate_;
   views_delegate_ = nullptr;
   delete platform_;
   platform_ = nullptr;
+#if defined(USE_AURA) && !defined(OS_CHROMEOS)
+  delete wm_state_;
+  wm_state_ = nullptr;
+#endif
 }
 
 void Shell::PlatformCleanUp() {
 }
 
 void Shell::PlatformEnableUIControl(UIControl control, bool is_enabled) {
   if (headless_)
     return;
   ShellWindowDelegateView* delegate_view =
     static_cast<ShellWindowDelegateView*>(window_widget_->widget_delegate());
@@ skipping 87 matching lines @@
 void Shell::PlatformSetTitle(const base::string16& title) {
   if (headless_)
     return;
   ShellWindowDelegateView* delegate_view =
     static_cast<ShellWindowDelegateView*>(window_widget_->widget_delegate());
   delegate_view->SetWindowTitle(title);
   window_widget_->UpdateWindowTitle();
 }
 
 }  // namespace content