message: Sort variables by name in custom gradient for determinism
diff: @@ -373,8 +373,10 @@ def _graph_mode_decorator(f, args, kwargs):
  v.ref() for v in _get_dependent_variables(
  input_ops=filtered_input_tensors, output_ops=flat_result)
  ])
  - variables = list(
  - [v.deref() for v in variables_in_subgraph.union(variables_in_tape)])
  + variables = sorted(
  + [v.deref() for v in variables_in_subgraph.union(variables_in_tape)],
  + key=lambda v: v.name
  + )
  grad_argspec = tf_inspect.getfullargspec(grad_fn)
  variables_in_signature = ("variables" in grad_argspec.args or
  