Remove always-on --harmony-rest-parameters flag

test/mjsunit/es6/super.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --allow-natives-syntax
-// Flags: --harmony-destructuring-bind --harmony-rest-parameters --harmony-sloppy
+// Flags: --harmony-destructuring-bind --harmony-sloppy
 
 (function TestSuperNamedLoads() {
   function Base() { }
   function fBase() { }
   Base.prototype = {
     f() {
       return "Base " + this.toString();
     },
     x: 15,
     toString() {
@@ skipping 2190 matching lines @@
   }
   class Derived extends Base {
     constructor(x) {
       let r = (() => super(...[x]))();
       assertEquals(this, r);
     }
   }
   let d = new Derived(42);
   assertSame(42, d.x);
 })();