Add brace_style "none" option + tests for javascript, then cleanup all brace_style tests

Javascript side of fix for issue #538. The last 3 commits here are more of a cleanup + refactor,
so that there's a single block of tests for brace style instead of 4 big blocks to try and keep consistent.
I might be able to make the original change to the code and tests in python but don't trust my
rudimentary python skills to be the one to do the same refactor there if it's desired/needed.