State of the overlay branch (again)?

[Sebastian Sturm <s.sturm@arkona-technologies.de>]

Hi all,

I hope I'm not getting on anybody's nerves by repeatedly asking the same 
question, but a while ago I was asking about the state of the Emacs 
overlay branch 
(https://lists.gnu.org/archive/html/emacs-devel/2018-03/msg00565.html) 
because overlays are heavily used by some implementations of semantic 
highlighting (see emacs-ccls, lsp-mode).

Somehow I had thought that the noverlay branch had long since been 
merged with master but when I recently tried to find evidence for that 
merge, I couldn't find any.

So, is the new overlay functionality part of Emacs master (heavily 
renamed perhaps), or if not, is the merge still planned? If so, is there 
anything I could do to help speed up the merge process (as of yet I 
don't have any experience with the overlay mechanism or Emacs' C 
internals though)

thanks,
Sebastian