Componentization: fix SupplementTracing<0>::~SupplementTracing<0>(void) already defined.

Source/core/page/Page.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All Rights Reserved.
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * 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 585 matching lines @@
     , editorClient(nullptr)
     , dragClient(nullptr)
     , spellCheckerClient(nullptr)
 {
 }
 
 Page::PageClients::~PageClients()
 {
 }
 
+template class WillBeHeapSupplement<Page>;
+
 } // namespace blink