Uninline HTMLCollection / LiveNodeList's item() and length() member functions

Source/core/html/HTMLCollection.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Samsung Electronics. 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 @@
         OverridesItemAfter,
         DoesNotOverrideItemAfter,
     };
 
     static PassRefPtrWillBeRawPtr<HTMLCollection> create(ContainerNode& base, CollectionType);
     virtual ~HTMLCollection();
     virtual void invalidateCache(Document* oldDocument = 0) const OVERRIDE;
     void invalidateCacheForAttribute(const QualifiedName*) const;
 
     // DOM API
-    unsigned length() const { return m_collectionIndexCache.nodeCount(*this); }
-    Element* item(unsigned offset) const { return m_collectionIndexCache.nodeAt(*this, offset); }
+    unsigned length() const;
+    Element* item(unsigned offset) const;
     virtual Element* namedItem(const AtomicString& name) const;
     bool namedPropertyQuery(const AtomicString&, ExceptionState&);
     void namedPropertyEnumerator(Vector<String>& names, ExceptionState&);
 
     // Non-DOM API
     void namedItems(const AtomicString& name, WillBeHeapVector<RefPtrWillBeMember<Element> >&) const;
     bool isEmpty() const { return m_collectionIndexCache.isEmpty(*this); }
     bool hasExactlyOneItem() const { return m_collectionIndexCache.hasExactlyOneNode(*this); }
 
     // CollectionIndexCache API.
@@ skipping 96 matching lines @@
 {
     if (!attrName || shouldInvalidateTypeOnAttributeChange(invalidationType(), *attrName))
         invalidateCache();
     else if (*attrName == HTMLNames::idAttr || *attrName == HTMLNames::nameAttr)
         invalidateIdNameCacheMaps();
 }
 
 } // namespace
 
 #endif