message: Fix for importing functions with a control dependency on an op with no outputs
diff: @@ -29,6 +29,7 @@ from tensorflow.python.framework import test_util
  from tensorflow.python.framework import test_ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import math_ops
  +from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
  @@ -225,12 +226,15 @@ class FunctionDefToGraphDefTest(test.TestCase):
  def testControlDependencies(self):
  + v = variables.Variable(1)
  +
  @function.defun
  def fn(inp):
  + assign = v.assign(3, name="assign", read_value=False)
  x = constant_op.constant(2.0, name="x")
  # TODO(b/79881896): Test external control dependency once that's
  # supported.
  - with ops.control_dependencies([x, inp]):
  + with ops.control_dependencies([x, inp, assign]):
  constant_op.constant(3.0, name="y")
  return 4.0
  @@ -239,9 +243,10 @@ class FunctionDefToGraphDefTest(test.TestCase):
  func_graph = function_def_to_graph.function_def_to_graph(fdef)
  op = func_graph.get_operation_by_name("y")
  - self.assertEqual(len(op.control_inputs), 2)
  + self.assertEqual(len(op.control_inputs), 3)
  self.assertEqual(op.control_inputs[0].name, "x")
  self.assertEqual(op.control_inputs[1].name, "inp")
  + self.assertEqual(op.control_inputs[2].name, "assign")
  if __name__ == "__main__":
  