So my quick hack broke this:
To fix this and related issues, I finally took the step of unifying all builds and build information into a single Python data structure:
To fix this, then, you can wait for the next Galaxy dist or apply the above changeset manually.
Actually, there an easier way to fix this without patching your Galaxy installation. Builds will show up in the library dbkey box if there's a chromosome length file associated with the build. Chromosome length files are used in some format converters (e.g. wig/bedgraph-to-bigwig) and for visualization.
You can download len files by doing the following:
(1) Uncomment/add len_file_path to your universe.wsgi.ini file, e.g.:
len_file_path = tool-data/shared/ucsc/chrom
(2) Run these commands from your Galaxy install to download len files from UCSC:
python ./cron/build_chrom_db.py ./tool-data/shared/ucsc/chrom/
(3) Restart Galaxy.