message: Blacklist Case op from callback
diff: @@ -43,6 +43,7 @@ _STATELESS_IF_OP = b"StatelessIf"
  _SWITCH_OP = b"Switch"
  _VAR_HANDLE_OP = b"VarHandleOp"
  _WHILE_OP = b"While"
  +_CASE_OP = b"Case"
  class _NumpyFunctionCallback(object):
  @@ -80,8 +81,9 @@ class _NumpyFunctionCallback(object):
  for output in outputs:
  if compat.as_bytes(op_type) in (_ENTER_OP, _EXIT_OP, _IF_OP, _MERGE_OP,
  _NEXT_ITERATION_OP, _STATELESS_IF_OP,
  - _SWITCH_OP, _WHILE_OP, _IDENTITY_OP,
  - _VAR_HANDLE_OP, _PLACEHOLDER_OP):
  + _SWITCH_OP, _WHILE_OP, _CASE_OP,
  + _IDENTITY_OP, _VAR_HANDLE_OP,
  + _PLACEHOLDER_OP):
  # TODO(cais): Overriding the output of StatelessIf, If and While ops
  # currently fails with error. Investigate (b/139668453).
  # Avoid instrumenting Identity ops as well, as they are inserted
  