message: Make minimum padding size to 2 in tpu.repliate.
  XLA doesn't support the upperbound of dynamic dimension of 1. Make
  minumum padding size to 2.
diff: @@ -823,13 +823,19 @@ def _pad_all_input(inputs, padded_shapes):
  paddings = []
  for i, s in enumerate(padded_shape.dims):
  if need_padding[idx][i]:
  + # The minimum padded dimension size is 2 as XLA doesn't support size
  + # 1 dynamic size.
  + minimum_dynamic_dim_size = 2
  if s.value:
  # Pad to the given maximum value.
  - padding = [0, s.value - input_shape_tensor[i]]
  + max_dim_size = max(s.value, minimum_dynamic_dim_size)
  else:
  # If maximum value is not given, then pad to the maximum dimension
  # among all the cores.
  - padding = [0, maximum_shapes[idx][i] - input_shape_tensor[i]]
  + max_dim_size = math_ops.maximum(maximum_shapes[idx][i],
  + minimum_dynamic_dim_size)
  + # Pad to the given maximum value.
  + padding = [0, max_dim_size - input_shape_tensor[i]]
  else:
  padding = [0, 0]
  paddings.append(padding)
  