lib: move DEP0006 to end of life

This commit moves DEP0006, which has been runtime deprecated
since Node 0.11, to end of life status.

PR-URL: #25279
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>

Author: cjihrig

doc/api/deprecations.md

@@ -160,6 +160,9 @@ outside `node_modules` in order to better target developers, rather than users.
 ### DEP0006: child\_process options.customFds
 <!-- YAML
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/25279
+    description: End-of-Life.
   - version:
     - v4.8.6
     - v6.12.0
@@ -171,7 +174,7 @@ changes:
     description: Documentation-only deprecation.
 -->
 
-Type: Runtime
+Type: End-of-Life
 
 Within the [`child_process`][] module's `spawn()`, `fork()`, and `exec()`
 methods, the `options.customFds` option is deprecated. The `options.stdio`

lib/child_process.js

@@ -22,9 +22,7 @@
 'use strict';
 
 const util = require('util');
-const {
-  deprecate, convertToValidSignal, getSystemErrorName
-} = require('internal/util');
+const { convertToValidSignal, getSystemErrorName } = require('internal/util');
 const { isArrayBufferView } = require('internal/util/types');
 const debug = util.debuglog('child_process');
 const { Buffer } = require('buffer');
@@ -384,20 +382,6 @@ Object.defineProperty(exports.execFile, util.promisify.custom, {
   value: customPromiseExecFunction(exports.execFile)
 });
 
-const _deprecatedCustomFds = deprecate(
-  function deprecateCustomFds(options) {
-    options.stdio = options.customFds.map(function mapCustomFds(fd) {
-      return fd === -1 ? 'pipe' : fd;
-    });
-  }, 'child_process: options.customFds option is deprecated. ' +
-     'Use options.stdio instead.', 'DEP0006');
-
-function _convertCustomFds(options) {
-  if (options.customFds && !options.stdio) {
-    _deprecatedCustomFds(options);
-  }
-}
-
 function normalizeSpawnArguments(file, args, options) {
   validateString(file, 'file');
 
@@ -526,8 +510,6 @@ function normalizeSpawnArguments(file, args, options) {
     }
   }
 
-  _convertCustomFds(options);
-
   return {
     file: file,
     args: args,