tls: de-duplicate for TLSSocket methods

Similar approach is used for `TLSWrap`, where C++ handle methods are
mapped one-to-one in JS.

PR-URL: #22142
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

lib/_tls_wrap.js

@@ -591,10 +591,6 @@ TLSSocket.prototype.setMaxSendFragment = function setMaxSendFragment(size) {
   return this._handle.setMaxSendFragment(size) === 1;
 };
 
-TLSSocket.prototype.getTLSTicket = function getTLSTicket() {
-  return this._handle.getTLSTicket();
-};
-
 TLSSocket.prototype._handleTimeout = function() {
   this._emitTLSError(new ERR_TLS_HANDSHAKE_TIMEOUT());
 };
@@ -671,51 +667,25 @@ TLSSocket.prototype.getPeerCertificate = function(detailed) {
   return null;
 };
 
-TLSSocket.prototype.getFinished = function() {
-  if (this._handle)
-    return this._handle.getFinished();
-};
-
-TLSSocket.prototype.getPeerFinished = function() {
-  if (this._handle)
-    return this._handle.getPeerFinished();
-};
-
-TLSSocket.prototype.getSession = function() {
-  if (this._handle) {
-    return this._handle.getSession();
-  }
-
-  return null;
-};
-
-TLSSocket.prototype.isSessionReused = function() {
-  if (this._handle) {
-    return this._handle.isSessionReused();
-  }
-
-  return null;
-};
-
-TLSSocket.prototype.getCipher = function(err) {
-  if (this._handle) {
-    return this._handle.getCurrentCipher();
-  } else {
+// Proxy TLSSocket handle methods
+function makeSocketMethodProxy(name) {
+  return function socketMethodProxy(...args) {
+    if (this._handle)
+      return this._handle[name].apply(this._handle, args);
     return null;
-  }
-};
-
-TLSSocket.prototype.getEphemeralKeyInfo = function() {
-  if (this._handle)
-    return this._handle.getEphemeralKeyInfo();
+  };
+}
 
-  return null;
-};
+[
+  'getFinished', 'getPeerFinished', 'getSession', 'isSessionReused',
+  'getEphemeralKeyInfo', 'getProtocol', 'getTLSTicket'
+].forEach((method) => {
+  TLSSocket.prototype[method] = makeSocketMethodProxy(method);
+});
 
-TLSSocket.prototype.getProtocol = function() {
+TLSSocket.prototype.getCipher = function(err) {
   if (this._handle)
-    return this._handle.getProtocol();
-
+    return this._handle.getCurrentCipher();
   return null;
 };