message: [Go]: Allow code in the "master" branch to work against the latest C library
  (1.12)
  Fixes for now.
  A more principled way of ensuring that we don't end up in this situation
  as the Go API is updated to use new C API features remains to be investigated.
diff: @@ -123,13 +123,22 @@ func (th *TensorHandle) DeviceName() (string, error) {
  // BackingDeviceName returns the name of the device in whose memory the tensor
  // handle resides. This function will block till the operation that produces
  // `h` has completed.
  +//
  +// WARNING: The implementation currently returns the same as DeviceName().
  +// After TensoFlow 1.13's C library is released, this implementation will
  +// be updated to return what the documentation says!
  func (th *TensorHandle) BackingDeviceName() (string, error) {
  + // TODO(ashankar): Restore after TensorFlow 1.13 is released.
  + // See https://github.com/tensorflow/tensorflow/issues/23257#issuecomment-433751410
  + return th.DeviceName()
  + /*
  status := newStatus()
  name := C.TFE_TensorHandleBackingDeviceName(th.c, status.c)
  if err := status.Err(); err != nil {
  return "", err
  }
  return C.GoString(name), nil
  + */
  }
  // ToTensor returns the Tensor referenced by th. It may block if this tensor is
  