return original name in case of non-use (or might conflict, see 247.dont-mangle-overloaded-native.jsx)
unexpected situations during testing is an error, not TODO
refactor Makefile to amend the prev. commit
Merge branch 'kazuho/experiments/error-in-test-is-not-a-todo'
Merge branch 'master' into kazuho/experiments/minify2