Add a @parameterized.named_product which combines both named_parameters and product together.

[copybara-service]

Add a @parameterized.named_product which combines both named_parameters and product together.

Named Parameterized Test Cases of a Cartesian Product

Both named_parameters and product have useful features.
However, when using both, it can be difficult to ensure that generated test
cases retain useful names.

Here, we combine both approaches to create parameterized tests with both
generated permutations and human-readable names.

Example:

    @parameterized.named_product(
        [
          dict(
              testcase_name='five_mod_three_is_2',
              num=5,
              modulo=3,
              expected=2,
          ),
          dict(
              testcase_name='seven_mod_four_is_3',
              num=7,
              modulo=4,
              expected=3,
          ),
        ],
        [
            dict(testcase_name='int', dtype=int),
            dict(testcase_name='float', dtype=float),
        ]
    )
    def testModuloResult(self, num, modulo, expected, dtype):
      self.assertEqual(expected, dtype(num) % modulo)

  This would generate the test cases:

    testModuloResult_five_mod_three_is_2_int
    testModuloResult_five_mod_three_is_2_float
    testModuloResult_seven_mod_four_is_3_int
    testModuloResult_seven_mod_four_is_3_float