Upstreaming Facebook extensions

[David Soria Parra]

On Tue, Nov 14, 2017 at 10:36:36AM -0800, Jun Wu wrote:
> Excerpts from Matt Harbison's message of 2017-11-13 22:49:56 -0500:
> > OK, good to know.
> > 
> > So is upstreaming lfs in a single patch and marking it experimental a  
> > reasonable next step, or does this need to incubate in hg-experimental a  
> > bit more?  I didn't get it working outside of the tests (it said something  
> > about not having a common changegroup version), but it looks like there's  
> > some low hanging fruit like registering the config options, and tracking  
> > down some warning in url.py about an "unquoted realm" or similar.
> 
> There are some ongoing tweaks about transferring files in threads on
> Windows.  But I think it's fine to also have an upstream version. The format
> is considered stable.

I think we should upstream this. Besides the tweaks for transferring files there is
still work that needs to be done on UI, resumable downloads and additional
consistency checking.

One of the major things to work on if we upstream is how it interacts with largefiles.