Revert "url: make the context non-enumerable"

This reverts commit 5e1bf05, as it
causes major performance regressions during object construction.

Refs: nodejs#24218

PR-URL: nodejs#24495
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Daijiro Wachi <daijiro.wachi@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/internal/url.js

@@ -246,14 +246,7 @@ function onParseError(flags, input) {
 // Reused by URL constructor and URL#href setter.
 function parse(url, input, base) {
   const base_context = base ? base[context] : undefined;
-  // In the URL#href setter
-  if (!url[context]) {
-    Object.defineProperty(url, context, {
-      enumerable: false,
-      configurable: false,
-      value: new URLContext()
-    });
-  }
+  url[context] = new URLContext();
   _parse(input.trim(), -1, base_context, undefined,
          onParseComplete.bind(url), onParseError);
 }
@@ -1381,11 +1374,7 @@ function toPathIfFileURL(fileURLOrPath) {
 }
 
 function NativeURL(ctx) {
-  Object.defineProperty(this, context, {
-    enumerable: false,
-    configurable: false,
-    value: ctx
-  });
+  this[context] = ctx;
 }
 NativeURL.prototype = URL.prototype;