The source from this directory was copied from the vorbis 
git 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 vorbis v1.3.5-48-ge5b1378
from https://git.xiph.org/vorbis.git

Some files are renamed during the copy to prevent clashes with object
file names with other Mozilla libraries.