Remove attrs sky doesn't support.

sky/engine/core/dom/Element.h

 /*
  * 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)
  * Copyright (C) 2003-2011, 2013, 2014 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
@@ skipping 230 matching lines @@
     virtual bool supportsFocus() const;
     // Whether the node can actually be focused.
     bool isFocusable() const;
     bool isKeyboardFocusable() const;
     bool isMouseFocusable() const;
     void dispatchFocusEvent(Element* oldFocusedElement, FocusType);
     void dispatchBlurEvent(Element* newFocusedElement);
     void dispatchFocusInEvent(const AtomicString& eventType, Element* oldFocusedElement);
     void dispatchFocusOutEvent(const AtomicString& eventType, Element* newFocusedElement);
 
-    String title() const;
-
     bool matches(const String& selectors, ExceptionState&);
 
     DOMTokenList& classList();
 
     virtual bool canContainRangeEndPoint() const override { return true; }
 
     void setCustomElementDefinition(PassRefPtr<CustomElementDefinition>);
     CustomElementDefinition* customElementDefinition() const;
 
     bool isSpellCheckingEnabled() const;
@@ skipping 332 matching lines @@
     static PassRefPtr<T> create(const QualifiedName&, Document&)
 #define DEFINE_ELEMENT_FACTORY_WITH_TAGNAME(T) \
     PassRefPtr<T> T::create(const QualifiedName& tagName, Document& document) \
     { \
         return adoptRef(new T(tagName, document)); \
     }
 
 } // namespace
 
 #endif  // SKY_ENGINE_CORE_DOM_ELEMENT_H_