The source from this directory was copied from the libvorbis
subversion repository using the update.sh script. The only changes
made were those applied by update.sh and the addition/update of
Makefile.in and moz.build files for the Mozilla build system.
The upstream version used was libvorbis 1.3.4.
Some files are renamed during the copy to prevent clashes with object
file names with other Mozilla libraries.