This removes the cached check for EE.prototype.prependListener
because we can't have nice things. More specifically some
libraries will bundle their own event emitter implementation.
PR-URL: https://github.com/nodejs/node/pull/8018
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
