For the overwhelming majority of users, scripts are minified, rendering error locations mostly useless. Investigate the use of [[ http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/ | source maps ]] to retrieve the original locations.
- make the minifier emit source maps (or consider replacing it with another minifier, which might be the easier way of doing this - several minifiers, e.g. [[ https://github.com/mishoo/UglifyJS2/ | UglifyJS ]], support source map generation)
- add source map support to ResourceLoader (bug 45514) - note that RL wraps scripts with some custom JS, so source maps need to be adjusted