message: Fix asan issue reported by clang 5
diff: @@ -180,10 +180,10 @@ TEST(DestroyGuard_General)
  bool destroyed_flag_1 = false;
  bool destroyed_flag_2 = false;
  {
  - DestroyGuard<Foo> dg;
  Foo foo_1(&destroyed_flag_1);
  - dg.reset(&foo_1);
  Foo foo_2(&destroyed_flag_2);
  + DestroyGuard<Foo> dg;
  + dg.reset(&foo_1);
  dg.reset(&foo_2);
  CHECK(destroyed_flag_1);
  }
  