domains: fix issues with abort on uncaught

Do not abort the process if an error is thrown from within a domain, an
error handler is setup for the domain and --abort-on-uncaught-exception
was passed on the command line.

However, if an error is thrown from within the top-level domain's error
handler and --abort-on-uncaught-exception was passed on the command
line, make the process abort.

Fixes: https://github.com/joyent/node/issues/8631
Fixes: https://github.com/joyent/node/issues/8630
PR-URL: https://github.com/joyent/node/pull/8666


Reviewed-by: Trevor Norris <trev.norris@gmail.com>