title: Can't import frozen graph with BatchNorm layer
body: <p>I have trained a Keras model based on this <a href="https://github.com/bonlime/keras-deeplab-v3-plus" rel="noreferrer">repo</a>.</p>
  
  <p>After the training I save the model as checkpoint files like this:  </p>
  
  <pre><code> sess=tf.keras.backend.get_session() 
   saver = tf.train.Saver()
   saver.save(sess, current_run_path + '/checkpoint_files/model_{}.ckpt'.format(date))
  </code></pre>
  
  <p>Then I restore the graph from the checkpoint files and freeze it using the standard tf freeze_graph script. When I want to restore the frozen graph I get the following error:</p>
  
  <p><code>Input 0 of node Conv_BN_1/cond/ReadVariableOp/Switch was passed float from Conv_BN_1/gamma:0 incompatible with expected resource</code></p>
  
  <p>How can I fix this issue?</p>
  
  <p>Edit: My problem is related to <a href="https://stackoverflow.com/questions/51622411/cant-import-frozen-graph-after-adding-layers-to-keras-model/51644241">this</a> question. Unfortunately, I can't use the workaround. </p>
  
  <p>Edit 2:
  I have opened an issue on github and created a gist to reproduce the error.
  <a href="https://github.com/keras-team/keras/issues/11032" rel="noreferrer">https://github.com/keras-team/keras/issues/11032</a></p>