Summary:
@public
* In case of `ShadowTree` we just pass original old node as a `commit` method argument;
* In case of `ConcreteViewShadowNode` we just don't need that because diffing algorithm does not use that information anymore.
Reviewed By: mdvacca
Differential Revision: D8753906
fbshipit-source-id: b8555083c7e72e9b3c0f9a8065745946d4cf44c7