Summary:
## Rationale
- **Consistency with Static View Configs**: In Static View Configs, if there isn't a diff or process function, we do not generate a property for it.
- **Type-safety**: The [Flow type for attributes](https://fburl.com/code/tafncg5c), doesn't allow null diff/process functions.
Changelog: [Internal]
Reviewed By: yungsters
Differential Revision: D32152924
fbshipit-source-id: 4156158c5fe09868feec1a0c55aa411d2bd72a27