Promoted extension dependencies in vk.xml

The section "Extension Dependencies" of the spec has this bit of text:
> If a required extension has been promoted to another extension or to a core API version, then as a _general_ rule, the dependency is also satisfied by the promoted extension or core version. This will be true so long as any features required by the original extension are also required or enabled by the promoted extension or core version.
> [...]
> There is metadata in `vk.xml` describing some aspects of promotion, especially `requires`, `promotedto` and `deprecatedby` attributes of `` tags. However, the metadata does not yet fully describe this scenario. In the future, we may extend the XML schema to describe the full set of extensions and versions satisfying a dependency.

Has any work been done on the additions to vk.xml that are mentioned here? I'm using vk.xml to check and resolve dependencies automatically and having the full dependencies would be very helpful.