Optimize Object.seal and Object.preventExtensions

test/mjsunit/object-freeze.js

Index: test/mjsunit/object-freeze.js
diff --git a/test/mjsunit/object-freeze.js b/test/mjsunit/object-freeze.js
index a48251304d85c536c055261c88867f623df97d99..5d1f8b7c5b0abb092639c90945c70aec48753a44 100644
--- a/test/mjsunit/object-freeze.js
+++ b/test/mjsunit/object-freeze.js
@@ -339,3 +339,12 @@ obj.__proto__[1] = 1;
 assertEquals(1, obj[1]);
 Object.freeze(obj);
 assertThrows(function() { obj.unshift(); }, TypeError);
+
+// Sealing and then Freezing should do the right thing.
+var obj = { foo: 'bar', 0: 'element' };
+Object.seal(obj);
+assertTrue(Object.isSealed(obj));
+assertFalse(Object.isFrozen(obj));
+Object.freeze(obj);
+assertTrue(Object.isSealed(obj));
+assertTrue(Object.isFrozen(obj));