OperatorHandle::callBoxed/callUnboxed (#29330)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/29330
This makes for a nicer API, especially in backend fallback kernels who get an OperatorHandle instance and can directly call these methods on it.
ghstack-source-id: 94481322
Test Plan: unit tests stacked on top
Differential Revision: D18357424
fbshipit-source-id: fa8c638335f246c906c8e16186507b4c486afb3f
