In the next few commits I will be converting the various Merger identifier typedefs into newtypes; and once that's done, the kInvalidId constant will only be used internally and therefore does not need to be part of the public mlir::sparse_tensor namespace.
Depends On D146673
are you deliberately enforcing the ::mlir top level instead of relying on the using mlir::sparse_tensor with the shorter version of this?
(I assume yes, but just checking)