Follow jsc on not throwing when trying to add a property to a non-extensible object.

test/mjsunit/object-freeze.js

 // Copyright 2010 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 52 matching lines @@
 
 assertTrue(Object.isExtensible(obj));
 assertFalse(Object.isFrozen(obj));
 
 Object.freeze(obj);
 
 // Make sure we are no longer extensible.
 assertFalse(Object.isExtensible(obj));
 assertTrue(Object.isFrozen(obj));
 
-try {
-   obj.foo = 42;
-   assertUnreachable();
-} catch(e) {
-  assertTrue(/object is not extensible/.test(e));
-}
+obj.foo = 42;
+assertEquals(obj.foo, undefined);
 
 desc = Object.getOwnPropertyDescriptor(obj, 'x');
 assertFalse(desc.writable);
 assertFalse(desc.configurable);
 assertEquals(42, desc.value);
 
 desc = Object.getOwnPropertyDescriptor(obj, 'z');
 assertFalse(desc.writable);
 assertFalse(desc.configurable);
 assertEquals("foobar", desc.value);
 
 // Make sure that even if we try overwrite a value that is not writable, it is
-// not changed. 
+// not changed.
 obj.x = "tete";
 assertEquals(42, obj.x);
 obj.x = { get: function() {return 43}, set: function() {} };
 assertEquals(42, obj.x);
 
 // Test on accessors.
 var obj2 = {};
 function get() { return 43; };
 function set() {};
 Object.defineProperty(obj2, 'x', { get: get, set: set, configurable: true });
 
 desc = Object.getOwnPropertyDescriptor(obj2, 'x');
 assertTrue(desc.configurable);
 assertEquals(undefined, desc.value);
 assertEquals(set, desc.set);
 assertEquals(get, desc.get);
 
 assertTrue(Object.isExtensible(obj2));
 assertFalse(Object.isFrozen(obj2));
 Object.freeze(obj2);
 assertTrue(Object.isFrozen(obj2));
 assertFalse(Object.isExtensible(obj2));
 
 desc = Object.getOwnPropertyDescriptor(obj2, 'x');
 assertFalse(desc.configurable);
 assertEquals(undefined, desc.value);
 assertEquals(set, desc.set);
 assertEquals(get, desc.get);
 
-try {
-  obj2.foo = 42;
-  assertUnreachable();
-} catch(e) {
-  assertTrue(/object is not extensible/.test(e));
-}
+obj2.foo = 42;
+assertEquals(obj2.foo, undefined);
 
 
 // Test freeze on arrays.
 var arr = new Array(42,43);
 
 desc = Object.getOwnPropertyDescriptor(arr, '0');
 assertTrue(desc.configurable);
 assertTrue(desc.writable);
 assertEquals(42, desc.value);
 
@@ skipping 51 matching lines @@
 var obj5 = {};
 Object.defineProperty(obj5, 'x', {configurable: true, writable: false});
 Object.defineProperty(obj5, 'y', {configurable: false, writable: false});
 Object.preventExtensions(obj5);
 
 assertFalse(Object.isFrozen(obj5));
 
 // Make sure that Object.freeze returns the frozen object.
 var obj6 = {}
 assertTrue(obj6 === Object.freeze(obj6))