SpeechSynthesisUtterance([String text])

Source 

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