message: TST: check message of exception
diff: @@ -789,7 +789,8 @@ class SaverTest(test.TestCase):
  # Restore the saved value with different dtype
  # in the parameter nodes.
  save = saver_module.Saver({"v0": v0_wrong_dtype})
  - with self.assertRaises(errors.InvalidArgumentError):
  + with self.assertRaisesRegexp(errors.InvalidArgumentError,
  + "original dtype"):
  save.restore(sess, save_path)
  