message: fix tf_text_graph_common tensor_content type bug
diff: @@ -324,6 +324,6 @@ def writeTextGraph(modelPath, outputPath, outNodes):
  for node in graph_def.node:
  if node.op == 'Const':
  if 'value' in node.attr and node.attr['value'].tensor.tensor_content:
  - node.attr['value'].tensor.tensor_content = ''
  + node.attr['value'].tensor.tensor_content = b''
  tf.train.write_graph(graph_def, "", outputPath, as_text=True)
  