Use a bitmask for SVG render object types

Source/core/rendering/svg/RenderSVGGradientStop.h

 /*
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 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.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 16 matching lines @@
 
 class SVGGradientElement;
 class SVGStopElement;
 
 // This class exists mostly so we can hear about gradient stop style changes
 class RenderSVGGradientStop FINAL : public RenderObject {
 public:
     explicit RenderSVGGradientStop(SVGStopElement*);
     virtual ~RenderSVGGradientStop();
 
-    virtual bool isSVGGradientStop() const { return true; }
     virtual const char* renderName() const { return "RenderSVGGradientStop"; }
+    virtual SVGType getSVGType() const OVERRIDE { return IsSVGGradientStop; }
 
     virtual void layout();
 
     // This overrides are needed to prevent ASSERTs on <svg><stop /></svg>
     // RenderObject's default implementations ASSERT_NOT_REACHED()
     // https://bugs.webkit.org/show_bug.cgi?id=20400
     virtual LayoutRect clippedOverflowRectForRepaint(const RenderLayerModelObject*) const OVERRIDE { return LayoutRect(); }
     virtual FloatRect objectBoundingBox() const { return FloatRect(); }
     virtual FloatRect strokeBoundingBox() const { return FloatRect(); }
     virtual FloatRect repaintRectInLocalCoordinates() const { return FloatRect(); }
 
 protected:
     virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle);
 
 private:
     SVGGradientElement* gradientElement() const;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderSVGGradientStop, isSVGGradientStop());
 
 }
 
 #endif // RenderSVGGradientStop_h