Bump to v4.17.9.

_nodeUtil.js

@@ -15,6 +15,14 @@ define(['./_freeGlobal'], function(freeGlobal) {
   /** Used to access faster Node.js helpers. */
   var nodeUtil = (function() {
     try {
+      // Use `util.types` for Node.js 10+.
+      var types = freeModule && freeModule.require && freeModule.require('util').types;
+
+      if (types) {
+        return types;
+      }
+
+      // Legacy `process.binding('util')` for Node.js < 10.
       return freeProcess && freeProcess.binding && freeProcess.binding('util');
     } catch (e) {}
   }());