message: Fix bug in test_concrete_function_backprop test in load_test.py.
  Function used input_signature with one shape, but was called with another shape.  This doesn't raise an exception in eager mode, but it does raise an exception in graph mode.
diff: @@ -995,9 +995,10 @@ class LoadTest(test.TestCase, parameterized.TestCase):
  self.assertAllEqual([6],
  imported.f(constant_op.constant([3])).numpy())
  + @test_util.run_in_graph_and_eager_modes
  def test_concrete_function_backprop(self, cycles):
  @def_function.function(
  - input_signature=[tensor_spec.TensorSpec([None], dtypes.float32)])
  + input_signature=[tensor_spec.TensorSpec([], dtypes.float32)])
  def func(x):
  return x ** 2.
  root = tracking.AutoTrackable()
  @@ -1010,10 +1011,10 @@ class LoadTest(test.TestCase, parameterized.TestCase):
  output = function(inp)
  return tape.gradient(output, inp)
  - self.assertEqual(2., _compute_gradient(root.f).numpy())
  + self.assertAllEqual(2., _compute_gradient(root.f))
  # TODO(andresp): Fix exporting of loaded concrete functions as signatures.
  imported = cycle(root, cycles, signatures={})
  - self.assertEqual(2., _compute_gradient(imported.f).numpy())
  + self.assertAllEqual(2., _compute_gradient(imported.f))
  def test_revived_concrete_function_kwargs(self, cycles):
  