Implement inverse & invertSelf function in DOMMatrix & DOMMatrixReadOnly.

third_party/WebKit/Source/core/dom/DOMMatrix.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 DOMMatrix_h
 #define DOMMatrix_h
 
 #include "core/dom/DOMMatrixReadOnly.h"
 
 namespace blink {
@@ skipping 31 matching lines @@
 
     DOMMatrix* multiplySelf(DOMMatrix*);
     DOMMatrix* preMultiplySelf(DOMMatrix*);
     DOMMatrix* translateSelf(double tx, double ty, double tz = 0);
     DOMMatrix* scaleSelf(double scale, double ox = 0, double oy = 0);
     DOMMatrix* scale3dSelf(double scale, double ox = 0, double oy = 0, double oz = 0);
     DOMMatrix* scaleNonUniformSelf(double sx, double sy = 1, double sz = 1,
         double ox = 0, double oy = 0, double oz = 0);
     DOMMatrix* skewXSelf(double sx = 0);
     DOMMatrix* skewYSelf(double sy = 0);
+    DOMMatrix* invertSelf();
 
 private:
     DOMMatrix(const TransformationMatrix&, bool is2D = true);
 
     void setIs2D(bool value);
 };
 
 } // namespace blink
 
 #endif