Use union instead of overload fo DOMMatrix/DOMMatrixReadOnly

third_party/WebKit/Source/core/geometry/DOMMatrix.idl

 // 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.
 
 // https://dev.w3.org/fxtf/geometry/#DOMMatrix
 
 [
-    Constructor,
-    Constructor(DOMString transformList),
-    Constructor(sequence<unrestricted double> numberSequence),
+    Constructor(optional (DOMString or sequence<unrestricted double>) init),
     RaisesException=Constructor,
     Exposed=(Window,Worker),
     RuntimeEnabled=GeometryInterfaces,
 ] interface DOMMatrix : DOMMatrixReadOnly {
     [RaisesException, NewObject] static DOMMatrix fromMatrix(optional DOMMatrixInit other);
     [RaisesException, NewObject] static DOMMatrix fromFloat32Array(Float32Array array32);
     [RaisesException, NewObject] static DOMMatrix fromFloat64Array(Float64Array array64);
 
     // These attributes are simple aliases for certain elements of the 4x4 matrix
     inherit attribute unrestricted double a;
@@ skipping 44 matching lines @@
     DOMMatrix rotateAxisAngleSelf(optional unrestricted double x = 0,
                                   optional unrestricted double y = 0,
                                   optional unrestricted double z = 0,
                                   optional unrestricted double angle = 0);
     DOMMatrix skewXSelf(optional unrestricted double sx = 0);
     DOMMatrix skewYSelf(optional unrestricted double sy = 0);
     DOMMatrix invertSelf();
 
     [RaisesException] DOMMatrix setMatrixValue(DOMString transformList);
 };