Revert "Fix shape invariance issue in conv_internal()"
Revert "Fix shape invariance issue in conv_internal()"

This reverts commit 9e2bcade7a27e50af94c8ef532a1277126c7665e.

waterblue13/tensor2tensor,tensorflow/tensor2tensor,vthorsteinsson/tensor2tensor,vthorsteinsson/tensor2tensor,waterblue13/tensor2tensor,rsepassi/tensor2tensor,rsepassi/tensor2tensor,tensorflow/tensor2tensor,rsepassi/tensor2tensor,vthorsteinsson/tensor2tensor,vthorsteinsson/tensor2tensor,tensorflow/tensor2tensor,waterblue13/tensor2tensor,tensorflow/tensor2tensor,tensorflow/tensor2tensor,rsepassi/tensor2tensor