Use Document, rather than document element, for implicit root.

third_party/WebKit/Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 36 matching lines @@
 #include "core/css/resolver/StyleResolver.h"
 #include "core/css/resolver/StyleResolverParentScope.h"
 #include "core/css/resolver/StyleResolverStats.h"
 #include "core/dom/AXObjectCache.h"
 #include "core/dom/Attr.h"
 #include "core/dom/CSSSelectorWatch.h"
 #include "core/dom/ClientRect.h"
 #include "core/dom/ClientRectList.h"
 #include "core/dom/DatasetDOMStringMap.h"
 #include "core/dom/ElementDataCache.h"
-#include "core/dom/ElementIntersectionObserverData.h"
 #include "core/dom/ElementRareData.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/FirstLetterPseudoElement.h"
 #include "core/dom/Fullscreen.h"
 #include "core/dom/LayoutTreeBuilder.h"
 #include "core/dom/MutationObserverInterestGroup.h"
 #include "core/dom/MutationRecord.h"
 #include "core/dom/NamedNodeMap.h"
 #include "core/dom/NodeComputedStyle.h"
+#include "core/dom/NodeIntersectionObserverData.h"
 #include "core/dom/PresentationAttributeStyle.h"
 #include "core/dom/PseudoElement.h"
 #include "core/dom/ScriptableDocumentParser.h"
 #include "core/dom/SelectorQuery.h"
 #include "core/dom/StyleChangeReason.h"
 #include "core/dom/StyleEngine.h"
 #include "core/dom/Text.h"
 #include "core/dom/custom/CustomElement.h"
 #include "core/dom/custom/CustomElementRegistrationContext.h"
 #include "core/dom/shadow/InsertionPoint.h"
@@ skipping 2511 matching lines @@
             if (!exceptionState.hadException())
                 return newChild;
         }
         return nullptr;
     }
 
     exceptionState.throwDOMException(SyntaxError, "The value provided ('" + where + "') is not one of 'beforeBegin', 'afterBegin', 'beforeEnd', or 'afterEnd'.");
     return nullptr;
 }
 
-ElementIntersectionObserverData* Element::intersectionObserverData() const
+NodeIntersectionObserverData* Element::intersectionObserverData() const
 {
     if (elementRareData())
         return elementRareData()->intersectionObserverData();
     return nullptr;
 }
 
-ElementIntersectionObserverData& Element::ensureIntersectionObserverData()
+NodeIntersectionObserverData& Element::ensureIntersectionObserverData()
 {
     return ensureElementRareData().ensureIntersectionObserverData();
 }
 
 // Step 1 of http://domparsing.spec.whatwg.org/#insertadjacenthtml()
 static Element* contextElementForInsertion(const String& where, Element* element, ExceptionState& exceptionState)
 {
     if (equalIgnoringCase(where, "beforeBegin") || equalIgnoringCase(where, "afterEnd")) {
         Element* parent = element->parentElement();
         if (!parent) {
@@ skipping 1029 matching lines @@
 {
 #if ENABLE(OILPAN)
     if (hasRareData())
         visitor->trace(elementRareData());
     visitor->trace(m_elementData);
 #endif
     ContainerNode::trace(visitor);
 }
 
 } // namespace blink