Object.observe: Handle oldValue for elements with accessors properly.

test/mjsunit/harmony/object-observe.js

 // Copyright 2012 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 38 matching lines @@
     assertCalled: function() {
       assertEquals(1, this.callbackCount);
     },
     assertRecordCount: function(count) {
       this.assertCalled();
       assertEquals(count, this.records.length);
     },
     assertCallbackRecords: function(recs) {
       this.assertRecordCount(recs.length);
       for (var i = 0; i < recs.length; i++) {
+        print(i, JSON.stringify(this.records[i]), JSON.stringify(recs[i]))
         assertSame(this.records[i].object, recs[i].object);
         assertEquals('string', typeof recs[i].type);
         assertPropertiesEqual(this.records[i], recs[i]);
       }
     }
   };
 
   observer.callback = function(r) {
     assertEquals(undefined, this);
     assertEquals('object', typeof r);
@@ skipping 244 matching lines @@
 delete obj[1];
 obj[1] = 4;
 obj[1] = 4;  // ignored
 obj[1] = 5;
 Object.defineProperty(obj, "1", {value: 6});
 Object.defineProperty(obj, "1", {writable: false});
 obj[1] = 7;  // ignored
 Object.defineProperty(obj, "1", {value: 8});
 Object.defineProperty(obj, "1", {value: 7, writable: true});
 Object.defineProperty(obj, "1", {get: function() {}});
+Object.defineProperty(obj, "1", {get: function() {}});
 delete obj[1];
 delete obj[1];
 Object.defineProperty(obj, "1", {get: function() {}, configurable: true});
 Object.defineProperty(obj, "1", {value: 9, writable: true});
 obj[1] = 10;
 delete obj[1];
 Object.defineProperty(obj, "1", {value: 11, configurable: true});
 Object.deliverChangeRecords(observer.callback);
 observer.assertCallbackRecords([
   { object: obj, name: "1", type: "updated", oldValue: 1 },
   { object: obj, name: "1", type: "updated", oldValue: 2 },
   { object: obj, name: "1", type: "deleted", oldValue: 3 },
   { object: obj, name: "1", type: "new" },
   { object: obj, name: "1", type: "updated", oldValue: 4 },
   { object: obj, name: "1", type: "updated", oldValue: 5 },
   { object: obj, name: "1", type: "reconfigured", oldValue: 6 },
   { object: obj, name: "1", type: "updated", oldValue: 6 },
   { object: obj, name: "1", type: "reconfigured", oldValue: 8 },
   { object: obj, name: "1", type: "reconfigured", oldValue: 7 },
-  // TODO(observe): oldValue should not be present below.
-  { object: obj, name: "1", type: "deleted", oldValue: undefined },
+  { object: obj, name: "1", type: "reconfigured" },
+  { object: obj, name: "1", type: "deleted" },
   { object: obj, name: "1", type: "new" },
-  // TODO(observe): oldValue should be absent below, and type = "reconfigured".
-  { object: obj, name: "1", type: "updated", oldValue: undefined },
+  { object: obj, name: "1", type: "reconfigured" },
   { object: obj, name: "1", type: "updated", oldValue: 9 },
   { object: obj, name: "1", type: "deleted", oldValue: 10 },
   { object: obj, name: "1", type: "new" },
 ]);
 
 // Observing array length (including truncation)
 reset();
 var arr = ['a', 'b', 'c', 'd'];
 var arr2 = ['alpha', 'beta'];
 var arr3 = ['hello'];
@@ skipping 226 matching lines @@
 var array = {0: 1, 1: 2, 2: 3, length: 3};
 Object.observe(array, observer.callback);
 Array.prototype.splice.call(array, 1, 1, 4, 5);
 Object.deliverChangeRecords(observer.callback);
 observer.assertCallbackRecords([
   { object: array, name: '3', type: 'new' },
   { object: array, name: '1', type: 'updated', oldValue: 2 },
   { object: array, name: '2', type: 'updated', oldValue: 3 },
   { object: array, name: 'length', type: 'updated', oldValue: 3 },
 ]);