Remove isSupportedAttribute in svg

Source/core/svg/SVGSVGElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2010 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Google, Inc.
  *
  * 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 301 matching lines @@
                 StyleChangeReasonForTracing::fromAttribute(attrName));
         }
     }
 
     if (SVGFitToViewBox::isKnownAttribute(attrName)) {
         updateRelativeLengthsOrViewBox = true;
         if (LayoutObject* object = layoutObject())
             object->setNeedsTransformUpdate();
     }
 
-    SVGElement::InvalidationGuard invalidationGuard(this);
-
     if (updateRelativeLengthsOrViewBox
         || SVGZoomAndPan::isKnownAttribute(attrName)) {
+        SVGElement::InvalidationGuard invalidationGuard(this);

[Erik Dahlström (inactive), 2015/04/13 08:11:17]

Note that all the above branches sets updateRelativeLengthsOrViewBox=true, so
we'll hit this codepath for all of the attributes that are handled here.

         if (layoutObject())
             markForLayoutAndParentResourceInvalidation(layoutObject());
         return;
     }
 
     SVGGraphicsElement::svgAttributeChanged(attrName);
 }
 
 // FloatRect::intersects does not consider horizontal or vertical lines (because of isEmpty()).
 static bool intersectsAllowingEmpty(const FloatRect& r1, const FloatRect& r2)
@@ skipping 446 matching lines @@
     visitor->trace(m_width);
     visitor->trace(m_height);
     visitor->trace(m_translation);
     visitor->trace(m_timeContainer);
     visitor->trace(m_viewSpec);
     SVGGraphicsElement::trace(visitor);
     SVGFitToViewBox::trace(visitor);
 }
 
 } // namespace blink