Use non-legacy constructors for tensor deserialization. (#18750)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/18750
ghimport-source-id: f1475cfb67841c41d9867d4429ba9125d5c7dd07
Stack from [ghstack](https://github.com/ezyang/ghstack):
* #18751 Disallow changing the device of a tensor via set_.
* **#18750 Use non-legacy constructors for tensor deserialization.**
* #18749 Add device and dtype to storage.
Deserialization currently uses legacy constructors. This is bad because we need to maintain them, but there is a more immediate problem:
1) We are trying to implement device caching on TensorImpl to get rid of a virtual dispatch
2) This doesn't work if one is able to change the device of a Tensor underlying a Variable.
3) Deserialization does 2)
So the plan is to change deserialization, then enforce that we don't change the device out from underneath a Variable.
Differential Revision: D14729513
fbshipit-source-id: 090d6cdb375b94dc1bf4f554b2df243952b8cdc6
