Lazily allocate svg shape transforms, shrink RenderSVGShape by 44B

Source/platform/transforms/AffineTransform.h

Index: Source/platform/transforms/AffineTransform.h
diff --git a/Source/platform/transforms/AffineTransform.h b/Source/platform/transforms/AffineTransform.h
index 772653b7409ea3ddeee89ae91e6a92376eb07b64..5f6da760d83336c240d26c2724952797bb781db2 100644
--- a/Source/platform/transforms/AffineTransform.h
+++ b/Source/platform/transforms/AffineTransform.h
@@ -51,6 +51,8 @@ public:
 
     void setMatrix(double a, double b, double c, double d, double e, double f);
 
+    void setTransform(const AffineTransform& other) { setMatrix(other.m_transform); }
+
     void map(double x, double y, double& x2, double& y2) const;
 
     // Rounds the mapped point to the nearest integer value.