Arrow functions: Cleanup handling of the prototype property

test/mjsunit/harmony/arrow-functions.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: --harmony-arrow-functions
 
 // Arrow functions are like functions, except they throw when using the
 // "new" operator on them.
 assertEquals("function", typeof (() => {}));
 assertEquals(Function.prototype, Object.getPrototypeOf(() => {}));
-assertThrows("new (() => {})", TypeError);
+assertThrows(function() { new (() => {}); }, TypeError);
+assertFalse("prototype" in (() => {}));
 
 // Check the different syntax variations
 assertEquals(1, (() => 1)());
 assertEquals(2, (a => a + 1)(1));
 assertEquals(3, (() => { return 3; })());
 assertEquals(4, (a => { return a + 3; })(1));
 assertEquals(5, ((a, b) => a + b)(1, 4));
 assertEquals(6, ((a, b) => { return a + b; })(1, 5));
 
 // The following are tests from:
@@ skipping 17 matching lines @@
 
 // Statement body needs braces, must use 'return' explicitly if not void
 var evens = [0, 2, 4, 6, 8];
 assertEquals([1, 3, 5, 7, 9], evens.map(v => v + 1));
 
 var fives = [];
 [1, 2, 3, 4, 5, 6, 7, 8, 9, 10].forEach(v => {
   if (v % 5 === 0) fives.push(v);
 });
 assertEquals([5, 10], fives);