#4964 fingeringOrientations don't deal properly with omitted Fingering-stencils

[Thomas Morley]

fingeringOrientations don't deal properly with omitted Fingering-stencils

\version "2.19.47"

{
  \set fingeringOrientations = #'(left)
  <a-1>1
  \omit Fingering
  <a-1 cis'-2 >1
}

returns:
programming error: Infinity or NaN encountered
<a-1 cis="" -2="">1

The visible output is correct, though.

Interestingly

{
  \set fingeringOrientations = #'(left)
  <a-1>1
  \omit Fingering
  <a-1>1
}

is compiled without complaints.

[Thomas Morley]

Hmm, bad formatting

the terminal-output should read:

programming error: Infinity or NaN encountered
  <a
    -1 cis-2 >1