Remaining Tensor API fixes - dims() -> sizes() (#15743)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/15743
Remaining fixes so that D12812029 will compile
Reviewed By: dzhulgakov
Differential Revision: D13535559
fbshipit-source-id: 2c8b3403570c8c35ac8efe2d827233abc0e6e0d1
