Implement basic interfaces and attributes for DOMMatrix.

Source/core/dom/DOMMatrix.cpp

Index: Source/core/dom/DOMMatrix.cpp
diff --git a/Source/core/dom/DOMMatrix.cpp b/Source/core/dom/DOMMatrix.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..59b27ccf9fcece18644f4a4e4be5a3b4d25115a4
--- /dev/null
+++ b/Source/core/dom/DOMMatrix.cpp
@@ -0,0 +1,55 @@
+// 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.
+
+#include "config.h"
+#include "core/dom/DOMMatrix.h"
+
+namespace blink {
+
+DOMMatrix* DOMMatrix::create()
+{
+    return new DOMMatrix(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1);
+}
+
+DOMMatrix* DOMMatrix::create(DOMMatrixReadOnly* other)
+{
+    return new DOMMatrix(other->m11(), other->m12(), other->m13(), other->m14(),
+        other->m21(), other->m22(), other->m23(), other->m24(),
+        other->m31(), other->m32(), other->m33(), other->m34(),
+        other->m41(), other->m42(), other->m43(), other->m44(),
+        other->is2D());
+}
+
+DOMMatrix::DOMMatrix(double m11, double m12, double m13, double m14,
+    double m21, double m22, double m23, double m24,
+    double m31, double m32, double m33, double m34,
+    double m41, double m42, double m43, double m44,
+    bool is2D)
+{
+    m_matrix[0][0] = m11;
+    m_matrix[0][1] = m12;
+    m_matrix[0][2] = m13;
+    m_matrix[0][3] = m14;
+    m_matrix[1][0] = m21;
+    m_matrix[1][1] = m22;
+    m_matrix[1][2] = m23;
+    m_matrix[1][3] = m24;
+    m_matrix[2][0] = m31;
+    m_matrix[2][1] = m32;
+    m_matrix[2][2] = m33;
+    m_matrix[2][3] = m34;
+    m_matrix[3][0] = m41;
+    m_matrix[3][1] = m42;
+    m_matrix[3][2] = m43;
+    m_matrix[3][3] = m44;
+    m_is2D = is2D;
+}
+
+void DOMMatrix::setIs2D(bool value)
+{
+    if (m_is2D)
+        m_is2D = value;

[abarth-chromium, 2014/08/04 17:54:18]

m_is2D = m_is2D && value ?

This seems wrong.  Suppose the matrix becomes non-2D.  Now it can never become
2D again, even if it gets reset to the identity.

+}
+
+} // namespace blink