But we never use the From parameter. It seems strange that we actually throw `c` away. I think this code would work just as well with:
```scala
def forTraversableSubclass[T, C](isImmutable: Boolean = true)(implicit mf: ClassManifest[C], cbf: CanBuildFrom[Nothing, T, C]): Kryo = {
```
Would that cause any issue since we only use the `def apply(): Builder[T, C]` method?