Re: Uses horizontal skylines in accidental placement (issue 6489086)

[k-ohara5a5a]

https://codereview.appspot.com/6489086/diff/11/lily/accidental.cc
File lily/accidental.cc (right):

https://codereview.appspot.com/6489086/diff/11/lily/accidental.cc#newcode89
lily/accidental.cc:89: (my_stencil->smobbed_copy (), 0.0, Y_AXIS));
We need to check that my_stencil exists here, in case someone defines
new alterations and forgets to assign a glyph for one of them.

newPitchNames = #`(
   (c . ,(ly:make-pitch -1 0 NATURAL))
   (ceseh . ,(ly:make-pitch -1 0 1/9)))
#(ly:parser-set-note-names parser newPitchNames)
{c''2 ceseh''}

I'll add a test and push after a `make check`

https://codereview.appspot.com/6489086/