SpeechSynthesisUtterance([String text ])

Source 

@DomName('SpeechSynthesisUtterance.SpeechSynthesisUtterance')
@DocsEditable()
factory SpeechSynthesisUtterance([String text]) {
  return _blink.BlinkSpeechSynthesisUtterance.instance.constructorCallback_1_(text);
}