Make sure pages that are closing but not yet closed are still suspended.

third_party/WebKit/Source/core/page/ScopedPageSuspender.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 18 matching lines @@
 class Page;
 
 class CORE_EXPORT ScopedPageSuspender final {
   WTF_MAKE_NONCOPYABLE(ScopedPageSuspender);
   USING_FAST_MALLOC(ScopedPageSuspender);
 
  public:
   explicit ScopedPageSuspender();
   ~ScopedPageSuspender();
 
+ private:
+  friend class Page;
+
+  static void setSuspended(bool);
   static bool isActive();
 };
 
 }  // namespace blink
 
 #endif  // ScopedPageSuspender_h