title: tensorflow export model and run it on Android failed
body: <p>I train an model using tensorflow on gpu server(K40), and then I export the model using session bundle, and I could run the exported model on PC computer. But when I use it on android, an error occurs:</p>
  
  <p>tensorflow_jni.cc:184 Check failed: ::tensorflow::Status::OK() == (tensorflow::serving::GetDefaultSignature(bundle.meta_graph_def, &amp;signature)) (OK vs. Failed precondition: Expected signature Any type_url for: tensorflow.serving.Signatures. Got: type.googleapis.com/tensorflow.contrib.Signatures.)</p>
  
  <p>We are frustrated about this error, I have no idea what is wrong during the process?</p>