Remove closure-make-deps and closure-calculate-chunks

[cpcallen]

Since each chunk is basically just the files in a particular subdirectory (core/, blocks/, generators/*/) we shouldn't need to use closure-calculate-chunks to compute the command line arguments for Closure Compiler—and if we don't need closure-calculate-chunks then we also no longer need closure-make-deps, since the former is the only remaining consumer of the output from the latter.