We run frontend tests for dev and prod server. The main difference is that prod run of frontend tests use the minified version of third_party.js. Currently, when we run prod frontend tests we run the whole build process (build minified third_party.js, add hashes to filenames, add hashes to HTML, etc.), we should create an option in build.py to only build minified third_party.js and the call just that before the prod frontend tests.