On Chrome (probably in V8), there's an unfortunate bug where re-throwing an exception does not preserve the stack trace. This makes it super confusing and annoying to try to debug dnode callbacks which throw an unhandled exception.
This change is a really crude but helpful way to debug these problems: just print the stack trace on the console, so the developer has something to work with. Perhaps there's a better way?
Log console error when callback throws exception.
I believe this should be fixed now? http://code.google.com/p/chromium/issues/detail?id=60240