title: Error with converting keras graph model to tf.js
body: <p>I'm trying to convert a non-sequential keras .h5 model to tensorflow.js, but some weird things are happening. </p>
  
  <p>Running the tensorflowjs_converter in the command line converts it fine, but when I look into model.json, I see that it says </p>
  
  <p>"format": "layers-model"</p>
  
  <p>Why is it doing this? Shouldn't a non-sequential model be converted into a graph model?</p>