Calling Map etc without new should throw TypeError

test/mjsunit/harmony/proxies-example-membrane.js

 // Copyright 2011 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 267 matching lines @@
 assertEquals(3, wf3);
 assertEquals(6, wfx.a);
 assertEquals(7, wgx.aa);
 assertEquals(4, wh4.q);
 
 
 // An identity-preserving membrane. Adapted from:
 // http://wiki.ecmascript.org/doku.php?id=harmony:proxies#an_identity-preserving_membrane
 
 function createMembrane(wetTarget) {
-  var wet2dry = WeakMap();
-  var dry2wet = WeakMap();
+  var wet2dry = new WeakMap();
+  var dry2wet = new WeakMap();
 
   function asDry(obj) {
     registerObject(obj)
     print("asDry enter", str(obj))
     try {
       var x = asDry2(obj);
       registerObject(x, "dry");
       print("asDry exit", str(obj), "as", str(x));
       return x;
     } catch(e) {
@@ skipping 203 matching lines @@
 assertThrows(function() { w[1] }, Error)
 assertThrows(function() { w.c }, Error)
 assertThrows(function() { wb.bb }, Error)
 assertEquals(3, wr.a)
 assertThrows(function() { wf(4) }, Error)
 assertEquals(6, wfx.a)
 assertEquals(7, wgx.aa)
 assertThrows(function() { wh4.q }, Error)
 assertThrows(function() { ws5.x }, Error)
 assertThrows(function() { ws5x.y }, Error)