Unify processing of weak lists in heap.cc

src/api.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 6104 matching lines @@
 void v8::ArrayBuffer::Neuter() {
   i::Handle<i::JSArrayBuffer> obj = Utils::OpenHandle(this);
   i::Isolate* isolate = obj->GetIsolate();
   ApiCheck(obj->is_external(),
            "v8::ArrayBuffer::Neuter",
            "Only externalized ArrayBuffers can be neutered");
   LOG_API(obj->GetIsolate(), "v8::ArrayBuffer::Neuter()");
   ENTER_V8(isolate);
 
   for (i::Handle<i::Object> array_obj(obj->weak_first_array(), isolate);
-       *array_obj != i::Smi::FromInt(0);) {
+       !array_obj->IsUndefined();) {
     i::Handle<i::JSTypedArray> typed_array(i::JSTypedArray::cast(*array_obj));
     typed_array->Neuter();
     array_obj = i::handle(typed_array->weak_next(), isolate);
   }
   obj->Neuter();
 }
 
 
 size_t v8::ArrayBuffer::ByteLength() const {
   i::Isolate* isolate = Utils::OpenHandle(this)->GetIsolate();
@@ skipping 1820 matching lines @@
 
   v->VisitPointers(blocks_.first(), first_block_limit_);
 
   for (int i = 1; i < blocks_.length(); i++) {
     v->VisitPointers(blocks_[i], &blocks_[i][kHandleBlockSize]);
   }
 }
 
 
 } }  // namespace v8::internal