message: Add benchmark for tf.function with retrace
diff: @@ -1346,6 +1346,12 @@ class MicroBenchmarks(benchmarks_test_base.MicroBenchmarksBase):
  values.append(array_ops.zeros(shape=(1000,)))
  self._run(lambda: np.array([x.numpy() for x in values]), 1000)
  + def benchmark_function_trace(self):
  + @def_function.function
  + def func(x):
  + return x
  + self._run(lambda: (func(x) for x in range(1000)), 30000)
  +
  def _benchmarkFunctionWithResourceInputs(self, num_resources, num_iters):
  @def_function.function
  def add_all(*args):
  