Several mjsunit cleanups

test/mjsunit/es6/default-parameters.js

 // Copyright 2015 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: --harmony-default-parameters
-
 
 (function TestDefaults() {
   function f1(x = 1) { return x }
   assertEquals(1, f1());
   assertEquals(1, f1(undefined));
   assertEquals(2, f1(2));
   assertEquals(null, f1(null));
 
   function f2(x, y = x) { return x + y; }
   assertEquals(8, f2(4));
@@ skipping 339 matching lines @@
   assertThrows(function(){ eval("(x=1) => {'use strict';}") }, SyntaxError);
   assertThrows(
     function(){ eval("(class{foo(x=1) {'use strict';}});") }, SyntaxError);
 
   assertThrows(
     function(){ eval("function(a, x=1){'use strict';}") }, SyntaxError);
   assertThrows(function(){ eval("(a, x=1) => {'use strict';}") }, SyntaxError);
   assertThrows(
     function(){ eval("(class{foo(a, x=1) {'use strict';}});") }, SyntaxError);
 })();