Stage ES6 generators

test/mjsunit/es6/regress/regress-2681.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 28 matching lines @@
   yield 2;
 }
 
 var o = g();
 assertEquals({ value: 1, done: false }, o.next());
 
 flush_all_code();
 
 assertEquals({ value: 2, done: false }, o.next());
 assertEquals({ value: undefined, done: true }, o.next());