* ensure that UV_... props are constants
* improve error message ... the error message when passing
in `err >= 0` to `util._errnoException()` was less than
useful.
* refine uses of process.binding('uv')
PR-URL: https://github.com/nodejs/node/pull/14933
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
