1. @DomName('LengthValue.add')
  2. @DocsEditable()
  3. @Experimental()
LengthValue add(LengthValue other)

Source 

@DomName('LengthValue.add')
@DocsEditable()
@Experimental() // untriaged
LengthValue add(LengthValue other) =>
    _blink.BlinkLengthValue.instance.add_Callback_1_(this, other);