Re-enable Object.observe and add enforcement for security invariants.

test/mjsunit/es7/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 95 matching lines @@
     recordCreated = true;
     return "bar";
   },
   enumerable: true
 })
 
 
 // Object.observe
 assertThrows(function() { Object.observe("non-object", observer.callback); },
              TypeError);
+assertThrows(function() { Object.observe(this, observer.callback); },
+             TypeError);
 assertThrows(function() { Object.observe(obj, nonFunction); }, TypeError);
 assertThrows(function() { Object.observe(obj, frozenFunction); }, TypeError);
 assertEquals(obj, Object.observe(obj, observer.callback, [1]));
 assertEquals(obj, Object.observe(obj, observer.callback, [true]));
 assertEquals(obj, Object.observe(obj, observer.callback, ['foo', null]));
 assertEquals(obj, Object.observe(obj, observer.callback, [undefined]));
 assertEquals(obj, Object.observe(obj, observer.callback,
              ['foo', 'bar', 'baz']));
 assertEquals(obj, Object.observe(obj, observer.callback, []));
 assertEquals(obj, Object.observe(obj, observer.callback, undefined));
 assertEquals(obj, Object.observe(obj, observer.callback));
 
 // Object.unobserve
 assertThrows(function() { Object.unobserve(4, observer.callback); }, TypeError);
+assertThrows(function() { Object.unobserve(this, observer.callback); },
+             TypeError);
 assertThrows(function() { Object.unobserve(obj, nonFunction); }, TypeError);
 assertEquals(obj, Object.unobserve(obj, observer.callback));
 
 
 // Object.getNotifier
 var notifier = Object.getNotifier(obj);
 assertSame(notifier, Object.getNotifier(obj));
 assertEquals(null, Object.getNotifier(Object.freeze({})));
+assertThrows(function() { Object.getNotifier(this) }, TypeError);
 assertFalse(notifier.hasOwnProperty('notify'));
 assertEquals([], Object.keys(notifier));
 var notifyDesc = Object.getOwnPropertyDescriptor(notifier.__proto__, 'notify');
 assertTrue(notifyDesc.configurable);
 assertTrue(notifyDesc.writable);
 assertFalse(notifyDesc.enumerable);
 assertThrows(function() { notifier.notify({}); }, TypeError);
 assertThrows(function() { notifier.notify({ type: 4 }); }, TypeError);
 
 assertThrows(function() { notifier.performChange(1, function(){}); }, TypeError);
@@ skipping 919 matching lines @@
   observer.assertCallbackRecords([
     { object: obj, name: prop, type: "update", oldValue: 1 },
     { object: obj, name: prop, type: "update", oldValue: 4 },
     { object: obj, name: prop, type: "update", oldValue: 5 },
     { object: obj, name: prop, type: "update", oldValue: 6 },
     { object: obj, name: prop, type: "reconfigure" },
   ]);
   Object.unobserve(obj, observer.callback);
 }
 
+// TODO(rafaelw) Enable when ES6 Proxies are implemented
+/*
 function createProxy(create, x) {
   var handler = {
     getPropertyDescriptor: function(k) {
       for (var o = this.target; o; o = Object.getPrototypeOf(o)) {
         var desc = Object.getOwnPropertyDescriptor(o, k);
         if (desc) return desc;
       }
       return undefined;
     },
     getOwnPropertyDescriptor: function(k) {
@@ skipping 19 matching lines @@
         var got = changeRecords[i];
         var change = {object: handler.proxy, name: got.name, type: got.type};
         if ("oldValue" in got) change.oldValue = got.oldValue;
         Object.getNotifier(handler.proxy).notify(change);
       }
     },
   };
   Object.observe(handler.target, handler.callback);
   return handler.proxy = create(handler, x);
 }
+*/
 
 var objects = [
   {},
   [],
-  this,  // global object
   function(){},
   (function(){ return arguments })(),
   (function(){ "use strict"; return arguments })(),
   Object(1), Object(true), Object("bla"),
   new Date(),
   Object, Function, Date, RegExp,
   new Set, new Map, new WeakMap,
-  new ArrayBuffer(10), new Int32Array(5),
-  createProxy(Proxy.create, null),
-  createProxy(Proxy.createFunction, function(){}),
+  new ArrayBuffer(10), new Int32Array(5)
+// TODO(rafaelw) Enable when ES6 Proxies are implemented.
+//  createProxy(Proxy.create, null),
+//  createProxy(Proxy.createFunction, function(){}),
 ];
 var properties = ["a", "1", 1, "length", "setPrototype", "name", "caller"];
 
 // Cases that yield non-standard results.
 function blacklisted(obj, prop) {
   return (obj instanceof Int32Array && prop == 1) ||
          (obj instanceof Int32Array && prop === "length") ||
          (obj instanceof ArrayBuffer && prop == 1)
 }
 
@@ skipping 640 matching lines @@
     for (var n1 = 0; n1 < 3; ++n1)
       for (var n2 = 0; n2 < 3; ++n2)
         for (var i in mutation)
           TestFastElementsLength(mutation[i], b1 != 0, b2 != 0, 20*n1, 20*n2);
 
 for (var b1 = 0; b1 < 2; ++b1)
   for (var b2 = 0; b2 < 2; ++b2)
     for (var n = 0; n < 3; ++n)
       for (var i in mutationByIncr)
         TestFastElementsLength(mutationByIncr[i], b1 != 0, b2 != 0, 7*n, 7*n+1);