spawn_sync: move process.binding('spawn_sync') to internalBinding

[antsmartian]

Migration from process.binding to internalBinding (see : #22160)

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• commit message follows commit guidelines

[jasnell]

LGTM with good CITGM run

[jdalton]

Holding removals until migration is ironed out

[jasnell]

@antsmartian ... when you get a moment, can you rebase this on master then apply the following patch which will be necessary for this to proceed:

Author: James M Snell <jasnell@gmail.com>
Date:   Tue Aug 14 19:36:25 2018 -0700

    [Squash] add `process.binding('spawn_sync')` to fallthrough whitelist

diff --git a/lib/internal/bootstrap/node.js b/lib/internal/bootstrap/node.js
index 08daeb1915..ffae6e4cd9 100644
--- a/lib/internal/bootstrap/node.js
+++ b/lib/internal/bootstrap/node.js
@@ -327,7 +327,7 @@
     // that are whitelisted for access via process.binding()... this is used
     // to provide a transition path for modules that are being moved over to
     // internalBinding.
-    const internalBindingWhitelist = new SafeSet(['uv']);
+    const internalBindingWhitelist = new SafeSet(['uv', 'spawn_sync']);
     process.binding = function binding(name) {
       return internalBindingWhitelist.has(name) ?
         internalBinding(name) :
diff --git a/test/parallel/test-process-binding-internalbinding-whitelist.js b/test/parallel/test-process-binding-internalbinding-whitelist.js
index ece967a0b7..cc0119917d 100644
--- a/test/parallel/test-process-binding-internalbinding-whitelist.js
+++ b/test/parallel/test-process-binding-internalbinding-whitelist.js
@@ -7,3 +7,4 @@ const assert = require('assert');
 // Assert that whitelisted internalBinding modules are accessible via
 // process.binding().
 assert(process.binding('uv'));
+assert(process.binding('spawn_sync'));

[antsmartian]

@jasnell Yes I'm working on that. I was following up the PR : #22269, so knew its coming ! :)

[antsmartian]

@jasnell Now it should be good to go, thanks!

[antsmartian]

@jasnell Have rebased, can we get this merge, before I get an another conflict :) Thanks for your help.

[antsmartian]

Ok seeing a lint issue, let me fix that.

[lundibundi]

LGTM after lint fix.

[BridgeAR]

CI https://ci.nodejs.org/job/node-test-pull-request/17042/

[antsmartian]

Yet again conflicts, let me rebase it tonight.. sorry folks..

[targos]

Landed in 9c9c01f

[antsmartian]

@targos Thanks for rebasing, didn't find time to do it. Thanks a ton.