Adds decorators for Python References and extends Python Reference testing (#76945)
This PR does the following...
Tests:
- fixes test_type_promotion in test_binary_ufuncs to correctly generate scalar cpu tensors
- fixes test_python_reference_consistency to use the Python Reference's reference inputs
- extends Python reference testing to test_conj_view, test_neg_view, and test_neg_conj_view
- adds a NaN propagation sample input for elementwise unary and binary operations
- fixes the UnaryUfuncInfo class to properly register its reference inputs
- Updates the Python Reference OpInfos to skip error inputs when their behavior on scalar inputs is inconsistent with their reference operators
Code organization:
- moves elementwise type promotion functionality to prims.utils
Prims & Refs:
- fixes scalar cpu tensor handling by having them pass through broadcasting and device and shape checks
- adds two decorators, `elementwise_type_promotion_wrapper` and `out_wrapper`, the former allows for elementwise type promotion to be automated and the latter automatically adds the out kwarg and handles it properly
cc @ezyang who also had some thoughts on cpu scalar tensor handling
cc @chillee -- might want to use this new decorator as we converge decompositions and references
Pull Request resolved: https://github.com/pytorch/pytorch/pull/76945
Approved by: https://github.com/ngimel
