Convert UJS parser errors to real Errors so that the async-build pipeline detects them.
Convert UJS parser errors to real Errors so that the async-build pipeline detects them.

joshuabrown-ellation/libjass,Arnavion/libjass,joshuabrown-ellation/libjass,Arnavion/libjass,Arnavion/libjass,joshuabrown-ellation/libjass