First half of fix for Mozilla BZ #500254
First half of fix for Mozilla BZ #500254

Residue code was not checking that its partition books were books with
specified/populated value mappings.  Fuzzer twiddled the book table suck that a valid codebook was being swapped out for a codebook with no value mapping.



git-svn-id: 03f0f1727258f1959b7b485b30a676bafdb78148@16181 0101bb08-14d6-0310-b084-bc0e0c8e3800

fcoulombe/vorbis,fcoulombe/vorbis,soundcloud/vorbis,fcoulombe/vorbis,fcoulombe/vorbis,soundcloud/vorbis,soundcloud/vorbis