* upstream/master: (147 commits)
  Support Loading to GPU (pytorch#10710)
  More changes for hidden visibility (pytorch#10692)
  Add arguments __repr__ in Distribution base class
  Add util function from core type to dtype (pytorch#10716)
  Make ONNX_ATEN_FALLBACK as internal default option
  Set the BUILD_ENVIRONMENT variable before installing sccache. (pytorch#10640)
  Avoid shadowing i, j vars in GeneralProposals test (pytorch#10721)
  Move THNN Reduction to ATen/core. (pytorch#10703)
  Completely remove build_aten and use_aten (pytorch#10469)
  Make empty list literals construct empty Tensor[] (pytorch#10705)
  Soumith's last few patches to v0.4.1
  Fix issues link in Caffe2 readme (pytorch#10711)
  Update the onnx Gemm op to FC/FCTransposed logic in caffe2 onnx backend (pytorch#10108)
  Adding ATEN_NO_TEST option to root level cmake for propogation to aten
  Allow method-style casts on tensors (pytorch#10641)
  Fix pytorch#10698 build failure (pytorch#10704)
  Add support for Log()
  Add a bisect percentile operator (pytorch#10563)
  Fix EnsureCPUOutputOp (pytorch#10651)
  Nomnigraph - rename some APIs that invole Subtree to Subgraph (pytorch#10551)
  ...

Summary:
Pull Request resolved: pytorch#10710

Can't resume from checkpoint for workflows that use GPU.

The problem is just we didn't leverage the already-provided GPU deserialization of Caffe2.

`keep_device` arg of LoadOp. See https://fburl.com/y27ltaxw

How a serialized BlobProto (contraining TensorProto) is loaded into GPU memory?
- Load BlobProto from DB. https://fburl.com/pe1qaeyf
- Deserialize the BlobProto into a Blob instance. https://fburl.com/5dirjuuh and https://fburl.com/stoho0x1
- Call Blob->Deserialized. https://fburl.com/bnureu32
- Deserializer Registration. https://fburl.com/wbu95ry7 https://fburl.com/ycetud8u
- Create TensorCUDA Deserializer. https://fburl.com/2lirfuqj
- Create Tensor on GPU and get TensorProto of BlobProto. https://fburl.com/7dre82zg
- Copy TensorProto in CPU to Tensor on GPU. https://fburl.com/fr0qk2oe

Cloned the GPU workflows for testing in D9125520.

Reviewed By: mraway

Differential Revision: D9372950

fbshipit-source-id: 2bf70747bd71e8da16239197f7d2761d63f09ff8