[operator] Add missing call to parent update method.
[operator] Add missing call to parent update method.

janmarthedal/mathml2svg,wavewave/lasem,janmarthedal/mathml2svg,wavewave/lasem,janmarthedal/mathml2svg,gjtorikian/lasem,gjtorikian/lasem,gjtorikian/lasem,wavewave/lasem,gjtorikian/lasem,wavewave/lasem,janmarthedal/mathml2svg