Creating an InstantiatedCapturedFunction that captures the instantiated state...

Creating an InstantiatedCapturedFunction that captures the instantiated state of a function to be executed, separating it out from the non instantiated regular state such as function name, captured inputs etc.

This allows us to truly separate Dataset kernel creation from Iterator creation i.e. each time a dataset is created that uses functions, we create only a CapturedFunction whereas we create an InstantiatedCapturedFunction each time a new iterator is created.

PiperOrigin-RevId: 213456128