Oilpan: move SVG property hierarchy to the heap.

Source/core/rendering/svg/RenderSVGResourcePattern.h

 /*
  * Copyright (C) 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  * Copyright 2014 The Chromium Authors. 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #ifndef RenderSVGResourcePattern_h
 #define RenderSVGResourcePattern_h
 
 #include "core/rendering/svg/RenderSVGResourcePaintServer.h"
 #include "core/svg/PatternAttributes.h"
 
+#include "platform/heap/Handle.h"
 #include "wtf/HashMap.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/RefPtr.h"
 
 namespace blink {
 
 class AffineTransform;
 class DisplayList;
 class FloatRect;
 class SVGPatternElement;
 struct PatternData;
 
 class RenderSVGResourcePattern final : public RenderSVGResourcePaintServer {
 public:
     explicit RenderSVGResourcePattern(SVGPatternElement*);
 
     virtual const char* renderName() const override { return "RenderSVGResourcePattern"; }
 
     virtual void removeAllClientsFromCache(bool markForInvalidation = true) override;
     virtual void removeClientFromCache(RenderObject*, bool markForInvalidation = true) override;
 
     virtual SVGPaintServer preparePaintServer(const RenderObject&) override;
 
     static const RenderSVGResourceType s_resourceType = PatternResourceType;
     virtual RenderSVGResourceType resourceType() const override { return s_resourceType; }
 
+    virtual void trace(Visitor*) override;
+
 private:
     PassOwnPtr<PatternData> buildPatternData(const RenderObject&);
     PassRefPtr<DisplayList> asDisplayList(const FloatRect& tileBounds, const AffineTransform&) const;
     PatternData* patternForRenderer(const RenderObject&);
 
     bool m_shouldCollectPatternAttributes : 1;
     PatternAttributes m_attributes;
 
     // FIXME: we can almost do away with this per-object map, but not quite: the tile size can be
     // relative to the client bounding box, and it gets captured in the cached Pattern shader.
     // Hence, we need one Pattern shader per client. The display list OTOH is the same => we
     // should be able to cache a single display list per RenderSVGResourcePattern + one
     // Pattern(shader) for each client -- this would avoid re-recording when multiple clients
     // share the same pattern.
     HashMap<const RenderObject*, OwnPtr<PatternData> > m_patternMap;
 };
 
 }
 
 #endif