message: Support approximateSize on db bigger than 4 GB
  By using napi_create_int64 instead of napi_create_int32.
  Closes
diff: @@ -1033,7 +1033,7 @@ struct ApproximateSizeWorker final : public PriorityWorker {
  void HandleOKCallback () override {
  napi_value argv[2];
  napi_get_null(env_, &argv[0]);
  - napi_create_uint32(env_, (uint32_t)size_, &argv[1]);
  + napi_create_int64(env_, (uint64_t)size_, &argv[1]);
  napi_value callback;
  napi_get_reference_value(env_, callbackRef_, &callback);
  CallFunction(env_, callback, 2, argv);
  