[clang-tools-extra] [clang-doc] Add DAG directive to MD "All files" test (PR #184671)

[Erick Velez via cfe-commits]

evelez7 wrote:

@ilovepi correct me if I'm wrong, but doesn't this not do anything now?

https://github.com/llvm/llvm-project/blob/149e62c29bf86b045ec8a9941c68ed2f13099b92/clang-tools-extra/clang-doc/Representation.cpp#L475-L479

If you call Index.sort, it just calls this on its children and there's no sorting actually happening. So depending on how your machine sorts it might be different from mine.

https://github.com/llvm/llvm-project/pull/184671