Use tf.contrib.eager.in_eager_mode()
Use tf.contrib.eager.in_eager_mode()

PiperOrigin-RevId: 195304327

vthorsteinsson/tensor2tensor,tensorflow/tensor2tensor,tensorflow/tensor2tensor,vthorsteinsson/tensor2tensor,tensorflow/tensor2tensor,tensorflow/tensor2tensor,vthorsteinsson/tensor2tensor,vthorsteinsson/tensor2tensor,tensorflow/tensor2tensor