Implement toString() funtion in DOMMatrixReadOnly.

third_party/WebKit/Source/core/dom/DOMMatrixReadOnly.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef DOMMatrixReadOnly_h
 #define DOMMatrixReadOnly_h
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/dom/DOMTypedArray.h"
@@ skipping 43 matching lines @@
     DOMMatrix* scale(double scale, double ox = 0, double oy = 0);
     DOMMatrix* scale3d(double scale, double ox = 0, double oy = 0, double oz = 0);
     DOMMatrix* scaleNonUniform(double sx, double sy = 1, double sz = 1,
         double ox = 0, double oy = 0, double oz = 0);
     DOMMatrix* flipX();
     DOMMatrix* flipY();
 
     DOMFloat32Array* toFloat32Array() const;
     DOMFloat64Array* toFloat64Array() const;
 
+    const AtomicString toString() const;

[pdr., 2016/08/23 18:24:30]

Can you use String here instead of AtomicString? I think it'll be slightly
faster because we don't really need the AtomicString machinery here.

[Hwanseung Lee, 2016/08/23 21:35:01]

it was changed to String instead of AtomicString.

+
     const TransformationMatrix& matrix() const { return *m_matrix; }
 
     DEFINE_INLINE_TRACE() { }
 
 protected:
     DOMMatrixReadOnly() {}
     // TransformationMatrix needs to be 16-byte aligned. PartitionAlloc
     // supports 16-byte alignment but Oilpan doesn't. So we use an std::unique_ptr
     // to allocate TransformationMatrix on PartitionAlloc.
     // TODO(oilpan): Oilpan should support 16-byte aligned allocations.
     std::unique_ptr<TransformationMatrix> m_matrix;
     bool m_is2D;
 
 private:
     DOMMatrixReadOnly(Vector<double> sequence);
 };
 
 } // namespace blink
 
 #endif