Simplify ActionCable.getConfig, Connection#getProtocol, and Connection#close

by relying on the implicit undefined return value

actioncable/app/assets/javascripts/action_cable.js

@@ -191,8 +191,8 @@
       if (!allowReconnect) {
         this.monitor.stop();
       }
-      if (this.isActive()) {
-        return this.webSocket ? this.webSocket.close() : undefined;
+      if (this.isActive() && this.webSocket) {
+        return this.webSocket.close();
       }
     };
     Connection.prototype.reopen = function reopen() {
@@ -211,7 +211,9 @@
       }
     };
     Connection.prototype.getProtocol = function getProtocol() {
-      return this.webSocket ? this.webSocket.protocol : undefined;
+      if (this.webSocket) {
+        return this.webSocket.protocol;
+      }
     };
     Connection.prototype.isOpen = function isOpen() {
       return this.isState("open");
@@ -458,7 +460,9 @@
   }
   function getConfig(name) {
     var element = document.head.querySelector("meta[name='action-cable-" + name + "']");
-    return element ? element.getAttribute("content") : undefined;
+    if (element) {
+      return element.getAttribute("content");
+    }
   }
   function createWebSocketURL(url) {
     if (url && !/^wss?:/i.test(url)) {

actioncable/app/javascript/action_cable/connection.js

@@ -44,7 +44,9 @@ class Connection {
 
   close({allowReconnect} = {allowReconnect: true}) {
     if (!allowReconnect) { this.monitor.stop() }
-    if (this.isActive()) { return (this.webSocket ? this.webSocket.close() : undefined) }
+    if (this.isActive() && this.webSocket) {
+      return this.webSocket.close()
+    }
   }
 
   reopen() {
@@ -65,7 +67,9 @@ class Connection {
   }
 
   getProtocol() {
-    return (this.webSocket ? this.webSocket.protocol : undefined)
+    if (this.webSocket) {
+      return this.webSocket.protocol
+    }
   }
 
   isOpen() {

actioncable/app/javascript/action_cable/index.js

@@ -24,7 +24,9 @@ export function createConsumer(url = getConfig("url") || INTERNAL.default_mount_
 
 export function getConfig(name) {
   const element = document.head.querySelector(`meta[name='action-cable-${name}']`)
-  return (element ? element.getAttribute("content") : undefined)
+  if (element) {
+    return element.getAttribute("content")
+  }
 }
 
 export function createWebSocketURL(url) {