message: Add back tests for converted_func
diff: @@ -30,6 +30,7 @@ from tensorflow.core.protobuf import config_pb2
  from tensorflow.core.protobuf import rewriter_config_pb2
  from tensorflow.python.compiler.tensorrt import trt_convert
  from tensorflow.python.eager import def_function
  +from tensorflow.python.eager import wrap_function
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import graph_util
  @@ -359,6 +360,17 @@ class TrtConvertTest(test_util.TensorFlowTestCase):
  converter = self._CreateConverterV2(input_saved_model_dir)
  converter.convert()
  + # Verify the converted GraphDef and ConcreteFunction.
  + @def_function.function
  + def wrapper_converted_func(*args, **kwargs):
  + return converter._converted_func(*args, **kwargs)
  + converted_func = wrapper_converted_func
  + self.assertIsInstance(converted_func, def_function.Function)
  + converted_concrete_func = converted_func.get_concrete_function(
  + tensor_spec.TensorSpec(shape=[None, 1, 1], dtype=dtypes.float32),
  + tensor_spec.TensorSpec(shape=[None, 1, 1], dtype=dtypes.float32))
  + self._CheckTrtOps(converted_concrete_func)
  +
  # Save the converted model without any TRT engine cache.
  output_saved_model_dir = self.mkdtemp()
  converter.save(output_saved_model_dir)
  @@ -433,6 +445,17 @@ class TrtConvertTest(test_util.TensorFlowTestCase):
  def _CheckFn(node):
  self.assertTrue(len(node.attr["serialized_segment"].s), node.name)
  + # Verify the converted GraphDef and ConcreteFunction.
  + @def_function.function
  + def wrapper_converted_func(*args, **kwargs):
  + return converter._converted_func(*args, **kwargs)
  + converted_func = wrapper_converted_func
  + self.assertIsInstance(converted_func, def_function.Function)
  + converted_concrete_func = converted_func.get_concrete_function(
  + tensor_spec.TensorSpec(shape=[None, 1, 1], dtype=dtypes.float32),
  + tensor_spec.TensorSpec(shape=[None, 1, 1], dtype=dtypes.float32))
  + self._CheckTrtOps(converted_concrete_func, _CheckFn)
  +
  # Save the converted model with the statically-built engine inlined.
  output_saved_model_dir = self.mkdtemp()
  converter.save(output_saved_model_dir)
  