process: register the inspector async hooks in bootstrap/node.js

So it's easier to tell the side effects of this setup.

PR-URL: nodejs#25443
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>

Author: joyeecheung

lib/internal/bootstrap/node.js

@@ -151,7 +151,11 @@ function startup() {
   }
 
   if (config.hasInspector) {
-    NativeModule.require('internal/inspector_async_hook').setup();
+    const {
+      enable,
+      disable
+    } = NativeModule.require('internal/inspector_async_hook');
+    internalBinding('inspector').registerAsyncHook(enable, disable);
   }
 
   // If the process is spawned with env NODE_CHANNEL_FD, it's probably

lib/internal/inspector_async_hook.js

@@ -1,16 +1,10 @@
 'use strict';
 
-const inspector = internalBinding('inspector');
-
-if (!inspector || !inspector.asyncTaskScheduled) {
-  exports.setup = function() {};
-  return;
-}
-
 let hook;
 let config;
 
 function lazyHookCreation() {
+  const inspector = internalBinding('inspector');
   const { createHook } = require('async_hooks');
   config = internalBinding('config');
 
@@ -72,6 +66,7 @@ function disable() {
   hook.disable();
 }
 
-exports.setup = function() {
-  inspector.registerAsyncHook(enable, disable);
+module.exports = {
+  enable,
+  disable
 };