message: Fix warning in constrained_optimization test
  In constrained_optimization test, keep_dims was
  used for reduce_sum. Since keep_dims has been deprecated
  it generates unnecessary warning. This fix updates
  keep_dims -> keepdims to disable the warning.
diff: @@ -169,8 +169,8 @@ def _project_stochastic_matrix_wrt_euclidean_norm(matrix):
  del old_inactive # Needed by the condition, but not the body.
  iteration += 1
  scale = (1.0 - standard_ops.reduce_sum(
  - matrix, axis=0, keep_dims=True)) / standard_ops.maximum(
  - 1.0, standard_ops.reduce_sum(inactive, axis=0, keep_dims=True))
  + matrix, axis=0, keepdims=True)) / standard_ops.maximum(
  + 1.0, standard_ops.reduce_sum(inactive, axis=0, keepdims=True))
  matrix += scale * inactive
  new_inactive = standard_ops.to_float(matrix > 0)
  matrix *= new_inactive
  