http: use kEmptyObject

PR-URL: nodejs/node#43159
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>

Author: LiviaMedeiros

lib/_http_agent.js

@@ -54,7 +54,10 @@ const {
     ERR_OUT_OF_RANGE,
   },
 } = require('internal/errors');
-const { once } = require('internal/util');
+const {
+  kEmptyObject,
+  once,
+} = require('internal/util');
 const {
   validateNumber,
   validateOneOf,
@@ -217,7 +220,7 @@ Agent.defaultMaxSockets = Infinity;
 Agent.prototype.createConnection = net.createConnection;
 
 // Get the key for a given set of request options
-Agent.prototype.getName = function getName(options = {}) {
+Agent.prototype.getName = function getName(options = kEmptyObject) {
   let name = options.host || 'localhost';
 
   name += ':';

lib/_http_client.js

@@ -43,7 +43,10 @@ const {
 
 const net = require('net');
 const assert = require('internal/assert');
-const { once } = require('internal/util');
+const {
+  kEmptyObject,
+  once,
+} = require('internal/util');
 const {
   _checkIsHttpToken: checkIsHttpToken,
   freeParser,
@@ -127,7 +130,7 @@ function ClientRequest(input, options, cb) {
 
   if (typeof options === 'function') {
     cb = options;
-    options = input || {};
+    options = input || kEmptyObject;
   } else {
     options = ObjectAssign(input || {}, options);
   }