async package-listing doesn't handle certificate problems

[chad]

I’m trying to update packages on a recent build from master, and the
certificate for Marmalade has expired.  I’m asked, roughly, to connect
anyway, connect just once, or not connect. When I chose N - don’t
connect, with debug-on-error 't, I get the stack trace I’ve abbreviated
below.  If I unset debug-on-error or continue from the debugger,
then “U" in the package list gives me "Waiting for the refresh to
finish…", forever.

This looks like a tricky case, but it seems to be almost working,
so I thought I’d mention it here. I can file a bug if you’d prefer.

Thanks,
~Chad


Debugger entered--Lisp error: (error "Could not create connection to 
marmalade-repo.org:443")
  signal(error ("Could not create connection to marmalade-repo.org:443"))
  error("Could not create connection to %s:%d" "marmalade-repo.org" 443)
  url-http([cl-struct-url "https" nil nil "marmalade-repo.org" nil 
"/packages/archive-contents”...