buffer: clean up usage of __proto__
buffer: clean up usage of __proto__

Prefer using Object.setPrototypeOf() instead.

PR-URL: https://github.com/nodejs/node/pull/3080
Reviewed-By: Ben Noordhuis <59bd0a3ff43b32849b319e645d4798d8a5d1e889@bnoordhuis.nl>

dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node