Add query and synchronize to c10::Stream (#59560)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/59560
`at::cuda::CUDAStream` has the `query` and `synchronize` methods, but `c10::Stream` does not, and I couldn't find any generic way to accomplish this. Hence I added helpers to do this to the DeviceGuardImpl interface, and then defined these methods on `c10::Stream`. (I had to do it out-of-line to circumvent a circular dependency).
ghstack-source-id: 130932249
Test Plan: CI
Reviewed By: ezyang
Differential Revision: D28931377
fbshipit-source-id: cd0c19cf021e305d0c0cf9af364afb445d010248
