convert-ly does not provide a compilable result

[Noeck]

Hi,

perhaps I am too demanding, but shouldn't this syntax be updated by
convert-ly?


\version "2.16.0"

\paper {
  system-system-spacing #'padding = #7
  nonstaff-nonstaff-spacing #'padding = #8
}

\markup \null


Running convert-ly (version 2.19.50) on it does not change the syntax
(except for the version number) but then running lilypond on it complains:

Fehler: syntax error, unexpected SCM_TOKEN, expecting '.' or '=' or ','
  system-system-spacing
                        #'padding = #7


I would expect convert-ly to update this to


\paper {
  system-system-spacing.padding = #7
  nonstaff-nonstaff-spacing.padding = #8
}

Best,
Joram