Replace caffe2::DeviceGuard with c10::cuda::CUDAGuard (#17623)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/17623
Despite it's generic sounding name, caffe2::DeviceGuard actually
only worked on CUDA devices. Rename it to something that more
clearly spells out its applicability.
I'm not sure if it's the right call, but in this patch I added
'using CUDAGuard = c10::cuda::CUDAGuard', as this seems to be more
in-line with how the Caffe2 codebase is currently written. More
idiomatic c10 namespace style would be to say cuda::CUDAGuard.
Willing to change this if people shout.
This is a respin of D13156470 (#14284)
Reviewed By: dzhulgakov
Differential Revision: D14285504
fbshipit-source-id: 93b8ab938b064572b3b010c307e1261fde0fff3d
