texmath-0.12.5: test/writer/mml/msub1.test

<<< native
[ ESub
    (EIdentifier "m")
    (EGrouped [ ENumber "1" , ESymbol Ord "\8291" , ENumber "2" ])
]
>>> mml
<?xml version='1.0' ?>
<math display="block" xmlns="http://www.w3.org/1998/Math/MathML">
  <msub>
    <mi>m</mi>
    <mrow>
      <mn>1</mn>
      <mi>&#8291;</mi>
      <mn>2</mn>
    </mrow>
  </msub>
</math>