Add a --harmony-object-observe runtime flag (on by default)

src/object-observe.js

Index: src/object-observe.js
diff --git a/src/object-observe.js b/src/object-observe.js
index 56859a1c97ba9f7729c2b8fb821c6142d6fdb7f1..6f4f20f078178d791c8b3ae3fb5474c53465cf55 100644
--- a/src/object-observe.js
+++ b/src/object-observe.js
@@ -10,6 +10,9 @@ var $observeNativeObjectObserve;
 var $observeNativeObjectGetNotifier;
 var $observeNativeObjectNotifierPerformChange;
 
+var $observeObjectMethods;
+var $observeArrayMethods;
+
 (function(global, utils) {
 
 "use strict";
@@ -676,20 +679,29 @@ function ObserveMicrotaskRunner() {
 
 // -------------------------------------------------------------------
 
-utils.InstallFunctions(GlobalObject, DONT_ENUM, [
+utils.InstallFunctions(notifierPrototype, DONT_ENUM, [
+  "notify", ObjectNotifierNotify,
+  "performChange", ObjectNotifierPerformChange
+]);
+
+$observeObjectMethods = [
   "deliverChangeRecords", ObjectDeliverChangeRecords,
   "getNotifier", ObjectGetNotifier,
   "observe", ObjectObserve,
   "unobserve", ObjectUnobserve
-]);
-utils.InstallFunctions(GlobalArray, DONT_ENUM, [
+];
+$observeArrayMethods = [
   "observe", ArrayObserve,
   "unobserve", ArrayUnobserve
-]);
-utils.InstallFunctions(notifierPrototype, DONT_ENUM, [
-  "notify", ObjectNotifierNotify,
-  "performChange", ObjectNotifierPerformChange
-]);
+];
+
+// TODO(adamk): Figure out why this prototype removal has to
+// happen as part of initial snapshotting.
+var removePrototypeFn = function(f, i) {
+  if (i % 2 === 1) %FunctionRemovePrototype(f);
+};
+$observeObjectMethods.forEach(removePrototypeFn);
+$observeArrayMethods.forEach(removePrototypeFn);
 
 $observeNotifyChange = NotifyChange;
 $observeEnqueueSpliceRecord = EnqueueSpliceRecord;