add FlipX() and FlipY() funtion in DOMMatrixReadOnly.

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

Index: third_party/WebKit/Source/core/dom/DOMMatrixReadOnly.h
diff --git a/third_party/WebKit/Source/core/dom/DOMMatrixReadOnly.h b/third_party/WebKit/Source/core/dom/DOMMatrixReadOnly.h
index 1fe41206ea3f8837c12debd9a0a9363cc6c2b46a..c63802515cc07545e18a1bbfeb6f5d2b11ed0548 100644
--- a/third_party/WebKit/Source/core/dom/DOMMatrixReadOnly.h
+++ b/third_party/WebKit/Source/core/dom/DOMMatrixReadOnly.h
@@ -55,6 +55,8 @@ public:
     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;