The `src.meta` attribute does not exist, and even if it did the derivation does
not have a `rec` to reference it. This appears to be breaking all ofBorg meta
evaluation checks:
```
while evaluating the attribute 'homepage' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-0-gleber.ewr1.nix.ci/pkgs/misc/lilypond/fonts.nix:34:27:
undefined variable 'src' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-0-gleber.ewr1.nix.ci/pkgs/misc/lilypond/fonts.nix:34:18
```
https://gist.github.com/GrahamcOfBorg/cd87009bfee1a9c0d4f0d828b82ee09a
Fixes#10290. Lilypond finds its Guile libraries by looking at the path
in argv[0], so it should be hardcoded to the real absolute path to the
executable.
source regions which are substituded by the tool nix-repository-manager.
See http://github.com/MarcWeber/nix-repository-manager/raw/master/README.
sourceByName is called sourceFromHead now.
updates: MPlayerTrunk, haxe, neko, netsurf, cinelerra, ctags
cinelerra does no longer build due to Xorg update
svn path=/nixpkgs/trunk/; revision=18894
