1. @DomName('FontFaceSet.add')
  2. @DocsEditable()
  3. @Experimental()
FontFaceSet add(FontFace arg)

Source 

@DomName('FontFaceSet.add')
@DocsEditable()
@Experimental() // untriaged
FontFaceSet add(FontFace arg) =>
    _blink.BlinkFontFaceSet.instance.add_Callback_1_(this, arg);