In pre/post-process functions, don't require depth == hparams.hidden_size
In pre/post-process functions, don't require depth == hparams.hidden_size

PiperOrigin-RevId: 175244248

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