Move HTMLTagCollection to its own file

Source/core/dom/ContainerNode.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 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.
@@ skipping 27 matching lines @@
 #include "core/dom/NodeRenderStyle.h"
 #include "core/dom/NodeTraversal.h"
 #include "core/dom/ScriptForbiddenScope.h"
 #include "core/dom/SelectorQuery.h"
 #include "core/dom/StaticNodeList.h"
 #include "core/dom/shadow/ElementShadow.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/events/MutationEvent.h"
 #include "core/html/HTMLCollection.h"
 #include "core/html/HTMLFrameOwnerElement.h"
+#include "core/html/HTMLTagCollection.h"
 #include "core/html/RadioNodeList.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/rendering/InlineTextBox.h"
 #include "core/rendering/RenderText.h"
 #include "core/rendering/RenderTheme.h"
 #include "core/rendering/RenderView.h"
 
 namespace WebCore {
 
 using namespace HTMLNames;
@@ skipping 1228 matching lines @@
         return true;
 
     if (node->isElementNode() && toElement(node)->shadow())
         return true;
 
     return false;
 }
 #endif
 
 } // namespace WebCore