Store Object.observe state per-isolate rather than per-context

src/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 25 matching lines @@
   get: $WeakMap.prototype.get,
   has: $WeakMap.prototype.has
 }
 
 function createInternalWeakMap() {
   var map = new $WeakMap;
   map.__proto__ = InternalWeakMapProto;
   return map;
 }
 
-var observerInfoMap = createInternalWeakMap();
-var objectInfoMap = createInternalWeakMap();
+var objectObservationState = %GetObjectObservationState();
+if (IS_UNDEFINED(objectObservationState.observerInfoMap)) {
+  objectObservationState.observerInfoMap = createInternalWeakMap();

[Michael Starzinger, 2012/11/05 13:08:10]

This will make the WeakMap instantiated in this context globally reachable from
the whole isolate. Thereby the first context will be kept alive indefinitely.

+  objectObservationState.objectInfoMap = createInternalWeakMap();
+}
+var observerInfoMap = objectObservationState.observerInfoMap;
+var objectInfoMap = objectObservationState.objectInfoMap;
 
 function ObjectObserve(object, callback) {
   if (!IS_SPEC_OBJECT(object))
     throw MakeTypeError("observe_non_object", ["observe"]);
   if (!IS_SPEC_FUNCTION(callback))
     throw MakeTypeError("observe_non_function", ["observe"]);
   if (InternalObjectIsFrozen(callback))
     throw MakeTypeError("observe_callback_frozen");
 
   if (!observerInfoMap.has(callback)) {
@@ skipping 96 matching lines @@
 function SetupObjectObserve() {
   %CheckIsBootstrapping();
   InstallFunctions($Object, DONT_ENUM, $Array(
     "deliverChangeRecords", ObjectDeliverChangeRecords,
     "notify", ObjectNotify,  // TODO: Remove when getNotifier is implemented.
     "observe", ObjectObserve,
     "unobserve", ObjectUnobserve
   ));
 }
 
-SetupObjectObserve();
+SetupObjectObserve();