[RFC] vim-patch:babc6a1

On top of #1744.

Patch output:

```
patching file runtime/doc/autocmd.txt
patching file runtime/doc/tags
Reversed (or previously applied) patch detected!  Assume -R? [n] 
Apply anyway? [n] 
Skipping patch.
1 out of 1 hunk ignored -- saving rejects to file runtime/doc/tags.rej
patching file runtime/doc/todo.txt
Hunk #3 succeeded at 258 with fuzz 2 (offset -3 lines).
patching file runtime/filetype.vim
Hunk #2 succeeded at 1007 (offset -4 lines).
patching file runtime/indent/html.vim
patching file runtime/syntax/json.vim
patching file runtime/syntax/rst.vim
```

So no manual changes, only a conflict with `runtime/doc/tags` (which is not in Neovim's repo anyway).