Problem wit grace notes

[Zbyněk Burget]

Hi again,

I find one more problem. This time with grace notes at the beginning of 
score, where is multiple staves.
If one of staves begins with grace note {\grace, \appoggiatura, 
\acciaccatura), instrument name on first line is not printed and key, 
time and clef signs are printed unreasonably.
If more simultaneous StaffGoups are defined, missing instrument names 
(and unreasonably engraved key, time and clef signs) are at all staves 
in staff group, in which is staff with grace note.

Example:

\score {
  <<
    \new Staff {
      \set Staff.instrumentName = #"Instrument 1"
      \set Staff.shortInstrumentName = #"I1"
      \key d \major
      \time 2/2
      \relative c' {
        d4 e fis gis
        a1
      }
    }
    \new Staff {
      \set Staff.instrumentName = #"Instrument 2"
      \set Staff.shortInstrumentName = #"I2"
      \key d \major
      \time 2/2
      \relative c' {
        \grace c8 d4 d d d \break
        d1
      }
    }
  >>
  \layout {}
}