src: refactor CopyProperties to remove JS

CopyProperties() is refactored to use
the V8 5.5 DefineProperty() API call.
The change does not alter current behaviour.
It is a step prior to removing the function
CopyProperties, which becomes reduntant
after fixes of V8 SetNamedPropertyHandler
in 5.5. V8.

Strings used as property attributes
(value, enumerable etc) and accessors
are defined as persistent strings
in src/env.h

PR-URL: https://github.com/nodejs/node/pull/11102


Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>