Fix retainer profile test regression

src/heap-profiler.cc

 // Copyright 2009 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 130 matching lines @@
   }
 
   void VisitPointer(Object** o) {
     if ((*o)->IsFixedArray() && !inside_array_) {
       // Traverse one level deep for data members that are fixed arrays.
       // This covers the case of 'elements' and 'properties' of JSObject,
       // and function contexts.
       inside_array_ = true;
       FixedArray::cast(*o)->Iterate(this);
       inside_array_ = false;
-    } else {
+    } else if ((*o)->IsHeapObject()) {
       profile_->StoreReference(cluster_, HeapObject::cast(*o));
     }
   }
 
   void VisitPointers(Object** start, Object** end) {
     for (Object** p = start; p < end; p++) VisitPointer(p);
   }
 
  private:
   const JSObjectsCluster& cluster_;
@@ skipping 523 matching lines @@
   GlobalHandles::MakeWeak(handle.location(),
                           static_cast<void*>(stack.start()),
                           StackWeakReferenceCallback);
 }
 
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 
 } }  // namespace v8::internal