message: Clear shapes as a temporary fix for freezing
  New shape information in SavedModels (cl/346241008) plus some faulty shape update logic were causing issues. The more satisfying solution will be to not use freezing.
diff: @@ -1146,6 +1146,16 @@ def convert_variables_to_constants_from_session_graph(
  Returns:
  An optimized GraphDef.
  """
  + # TODO(b/176982859): Find a more satisfying way to update shape information
  + # than clearing it, or migrate users to a workflow that does not require
  + # freezing.
  + for function in graph_def.library.function:
  + if "_input_shapes" in function.attr:
  + for input_arg, shape_attribute in zip(
  + function.signature.input_arg,
  + function.attr["_input_shapes"].list.shape):
  + if dtypes.as_dtype(input_arg.type) == dtypes.resource:
  + shape_attribute.unknown_rank = True
  graph_def, _ = _replace_variables_by_constants(
  converter_data=_SessionConverterData(
  session=session,
  