Make supportsMarkers non virtual

Source/core/svg/SVGElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) 2009 Cameron McCormack <cam@mcc.id.au>
  *
  * 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 242 matching lines @@
     // If we aren't an instance in a <use> or the <use> title was not found, then find the first
     // <title> child of this element.
     // If a title child was found, return the text contents.
     if (Element* titleElement = Traversal<SVGTitleElement>::firstChild(*this))
         return titleElement->innerText();
 
     // Otherwise return a null/empty string.
     return String();
 }
 
+bool SVGElement::supportsMarkers() const
+{
+    DEFINE_STATIC_LOCAL(HashSet<AtomicString>, s_tagList, ());
+    if (s_tagList.isEmpty()) {
+        s_tagList.add(SVGNames::lineTag.localName());
+        s_tagList.add(SVGNames::pathTag.localName());
+        s_tagList.add(SVGNames::polygonTag.localName());
+        s_tagList.add(SVGNames::polylineTag.localName());
+    }
+
+    return s_tagList.contains(localName());

[f(malita), 2014/03/19 14:58:55]

We're replacing a virtual call with a hashset lookup during shape layout. Not
sure whether this is noticeable, but we should double check - can you run the
SVG perf tests locally and make sure we're not introducing regressions?

+}
+
 PassRefPtrWillBeRawPtr<CSSValue> SVGElement::getPresentationAttribute(const AtomicString& name)
 {
     if (!hasAttributesWithoutUpdate())
         return nullptr;
 
     QualifiedName attributeName(nullAtom, name, nullAtom);
     const Attribute* attr = getAttributeItem(attributeName);
     if (!attr)
         return nullptr;
 
@@ skipping 860 matching lines @@
         animatableAttributes.add(SVGNames::zAttr);
     }
 
     if (name == classAttr)
         return true;
 
     return animatableAttributes.contains(name);
 }
 #endif
 }