If JS throws an object whose toString() method throws, then Node
attempts to print an empty message, but actually prints garbage.
This commit checks for this case, and prints a message instead.
Fixes: https://github.com/nodejs/node/issues/4079
PR-URL: https://github.com/nodejs/node/pull/4112
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Chris Dickinson <christopher.s.dickinson@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Minwoo Jung <jmwsoft@gmail.com>
