\midi was ignored when fixes for issues 4302 and 4772 were committed to
\layout . This commit brings the context hierarchy in \midi back in
line with the state in \layout .
\accepts Lyrics
\accepts MensuralStaff
\accepts NoteNames
- \accepts NullVoice
\accepts OneStaff
\accepts PetrucciStaff
\accepts PianoStaff
\accepts ChordNames
\accepts FiguredBass
\accepts DrumStaff
+ \accepts Dynamics
\accepts GrandStaff
\accepts Lyrics
\accepts OneStaff