Attempt no. 3 to fix Heap::IsHeapIterable and HeapIterator

test/cctest/test-object-observe.cc

 // 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 598 matching lines @@
     LocalContext context2(CcTest::isolate());
     context2->SetSecurityToken(foo);
     context2->Global()->Set(String::NewFromUtf8(CcTest::isolate(), "obj"),
                             instance);
     CHECK(CompileRun("Object.getNotifier(obj)")->IsObject());
   }
 }
 
 
 static int GetGlobalObjectsCount() {
-  CcTest::heap()->EnsureHeapIsIterable();
   int count = 0;
   i::HeapIterator it(CcTest::heap());
   for (i::HeapObject* object = it.next(); object != NULL; object = it.next())
     if (object->IsJSGlobalObject()) count++;
   return count;
 }
 
 
 static void CheckSurvivingGlobalObjectsCount(int expected) {
   // We need to collect all garbage twice to be sure that everything
@@ skipping 73 matching lines @@
                             notifier);
     CompileRun("var obj2 = {};"
                "var notifier2 = Object.getNotifier(obj2);"
                "notifier2.performChange.call("
                    "notifier, 'foo', function(){})");
   }
 
   v8::V8::ContextDisposedNotification();
   CheckSurvivingGlobalObjectsCount(1);
 }