events: onceWrapper apply directly with arguments

Due to changes in V8 in 6.0 & 6.1, it's no longer necessary to copy
arguments to avoid deopt. Just call .apply with arguments. Retains
fast cases for 0-3 arguments.

events/ee-once-4-args.js n=20000000     11.58 %      *** 1.310379e-05

lib/events.js

@@ -327,10 +327,7 @@ function onceWrapper() {
         return this.listener.call(this.target, arguments[0], arguments[1],
                                   arguments[2]);
       default:
-        const args = new Array(arguments.length);
-        for (var i = 0; i < args.length; ++i)
-          args[i] = arguments[i];
-        this.listener.apply(this.target, args);
+        this.listener.apply(this.target, arguments);
     }
   }
 }