message: Match RaggedTensor enqueue behavior to SparseTensor when passed dense tensor.
diff: @@ -1392,16 +1392,20 @@ class TPUEmbedding(object):
  'table_ids': [],
  'max_sequence_lengths': [],
  }
  + int_zeros = array_ops.zeros((0,), dtype=dtypes.int64)
  + float_zeros = array_ops.zeros((0,), dtype=dtypes.float32)
  for table_id, table in enumerate(self._table_to_features_dict):
  features = self._table_to_features_dict[table]
  for feature in features:
  enqueue_data = enqueue_datas[feature]
  - kwargs['sample_splits'].append(enqueue_data.sample_splits)
  + kwargs['sample_splits'].append(
  + enqueue_data.sample_splits
  + if enqueue_data.sample_splits is not None else int_zeros)
  kwargs['aggregation_weights'].append(
  - enqueue_data.aggregation_weights if enqueue_data.aggregation_weights
  - is not None else array_ops.zeros((0,), dtype=dtypes.float32))
  + enqueue_data.aggregation_weights
  + if enqueue_data.aggregation_weights is not None else float_zeros)
  kwargs['embedding_indices'].append(enqueue_data.embedding_indices)
  