Add toFloat*Array() methods and use them in layout tests.

Source/core/dom/DOMMatrixReadOnly.h

Index: Source/core/dom/DOMMatrixReadOnly.h
diff --git a/Source/core/dom/DOMMatrixReadOnly.h b/Source/core/dom/DOMMatrixReadOnly.h
index e0460f384fefbeb39f016c3c7c7e6d5bffde74a4..f55b7b7f6cad5042b93f5338ac2906fb4afd1e51 100644
--- a/Source/core/dom/DOMMatrixReadOnly.h
+++ b/Source/core/dom/DOMMatrixReadOnly.h
@@ -8,6 +8,8 @@
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "platform/heap/Handle.h"
 #include "platform/transforms/TransformationMatrix.h"
+#include "wtf/Float32Array.h"
+#include "wtf/Float64Array.h"
 
 namespace blink {
 
@@ -48,6 +50,9 @@ public:
     DOMMatrix* scaleNonUniform(double sx, double sy = 1, double sz = 1,
         double ox = 0, double oy = 0, double oz = 0);
 
+    PassRefPtr<Float32Array> toFloat32Array() const;
+    PassRefPtr<Float64Array> toFloat64Array() const;
+
     const TransformationMatrix& matrix() const { return m_matrix; }
 
     void trace(Visitor*) { }