The externs listed here are for projects which use Closure Compiler to minify. I've written them, and I can't guarantee they are perfect, but they do stop the compiler from renaming critical symbols.
- [https://developers.google.com/closure/compiler/docs/api-tutorial3](Advanced Compilation and Externs)
- [http://code.google.com/p/closure-compiler/wiki/FAQ#How_do_I_write_an_externs_file?](How do I write an externs file?)