Oilpan: move SVG property hierarchy to the heap.

Source/core/rendering/svg/RenderSVGResourcePattern.h

Index: Source/core/rendering/svg/RenderSVGResourcePattern.h
diff --git a/Source/core/rendering/svg/RenderSVGResourcePattern.h b/Source/core/rendering/svg/RenderSVGResourcePattern.h
index 92da9a9303137a8f52717d403e097ff1bc5b6407..83a2c7a84c8ea54b3a4fdcfc32c305c0a7a01a06 100644
--- a/Source/core/rendering/svg/RenderSVGResourcePattern.h
+++ b/Source/core/rendering/svg/RenderSVGResourcePattern.h
@@ -25,6 +25,7 @@
 #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"
@@ -51,6 +52,8 @@ public:
     virtual RenderSVGResourceType resourceType() const override { return s_resourceType; }
     static const RenderSVGResourceType s_resourceType;
 
+    virtual void trace(Visitor*) override;
+
 private:
     PassOwnPtr<PatternData> buildPatternData(const RenderObject&);
     PassRefPtr<DisplayList> asDisplayList(const FloatRect& tileBounds, const AffineTransform&) const;