FB22524198: NSTextLayoutFragment.extraLineFragmentAttributes is private API that makes impossible calculate extra line fragment correctly

NSTextLayoutFragment does not expose extraLineFragmentAttributes property, that is used by the layout routine. Without setting the NSTextLayoutFragment.extraLineFragmentAttributes calculated height for the extra line fragment is broken and always default to a fallback value. Because NSTextLayoutFragment.extraLineFragmentAttributes is not public API, it is impossible to make the layout routine do correct/expected calculation for the frame.