[ASTContext] Profile Dependently-sized array types that do not have a specified number
of elements

Close https://github.com/llvm/llvm-project/issues/91105

The root reason for the issue is that we always generate the
dependently-sized array types which don't specify a number of elements.

The original comment says:

> We do no canonicalization here at all, which is okay
> because they can't be used in most locations.

But now we find the locations.

GitOrigin-RevId: f9d76197ff0099502cf001abe3f5310c5bc4532d
3 files changed