Remove viewportDefiningElement.

sky/engine/core/dom/Document.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 397 matching lines @@
     // The following implements the rule from HTML 4 for what valid names are.
     // To get this right for all the XML cases, we probably have to improve this or move it
     // and make it sensitive to the type of document.
     static bool isValidName(const String&);
 
     // The following breaks a qualified name into a prefix and a local name.
     // It also does a validity check, and returns false if the qualified name
     // is invalid.  It also sets ExceptionCode when name is invalid.
     static bool parseQualifiedName(const AtomicString& qualifiedName, AtomicString& prefix, AtomicString& localName, ExceptionState&);
 
-    // Decide which element is to define the viewport's overflow policy. If |rootStyle| is set, use
-    // that as the style for the root element, rather than obtaining it on our own. The reason for
-    // this is that style may not have been associated with the elements yet - in which case it may
-    // have been calculated on the fly (without associating it with the actual element) somewhere.
-    Element* viewportDefiningElement(RenderStyle* rootStyle = 0) const;
-
     DocumentMarkerController& markers() const { return *m_markers; }
 
     bool directionSetOnDocumentElement() const { return m_directionSetOnDocumentElement; }
     void setDirectionSetOnDocumentElement(bool b) { m_directionSetOnDocumentElement = b; }
 
     KURL openSearchDescriptionURL();
 
     Document& topDocument() const;
     WeakPtr<Document> contextDocument();
 
@@ skipping 350 matching lines @@
 Node* eventTargetNodeForDocument(Document*);
 
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showLiveDocumentInstances();
 #endif
 
 #endif  // SKY_ENGINE_CORE_DOM_DOCUMENT_H_