Oilpan: move SVG property hierarchy to the heap.

Source/core/html/canvas/CanvasRenderingContext2D.h

Index: Source/core/html/canvas/CanvasRenderingContext2D.h
diff --git a/Source/core/html/canvas/CanvasRenderingContext2D.h b/Source/core/html/canvas/CanvasRenderingContext2D.h
index 563d3ca5668e1f2d927fc17b90298c0f04815fbf..ff24d21b56cba28d7d82566921f25e85c3cd83a9 100644
--- a/Source/core/html/canvas/CanvasRenderingContext2D.h
+++ b/Source/core/html/canvas/CanvasRenderingContext2D.h
@@ -122,11 +122,11 @@ public:
     void save() { ++m_stateStack.last()->m_unrealizedSaveCount; }
     void restore();
 
-    PassRefPtr<SVGMatrixTearOff> currentTransform() const
+    PassRefPtrWillBeRawPtr<SVGMatrixTearOff> currentTransform() const
     {
         return SVGMatrixTearOff::create(state().m_transform);
     }
-    void setCurrentTransform(PassRefPtr<SVGMatrixTearOff>);
+    void setCurrentTransform(PassRefPtrWillBeRawPtr<SVGMatrixTearOff>);
 
     void scale(float sx, float sy);
     void rotate(float angleInRadians);