make-network-process: Breaks after recent update from GitHub

[raman@google.com (T.V Raman)]

Looks like that function went through some changes last week -- (july
9 etc) and a fresh build from GitHub results in the following call
failing:
(git blame shows both Stephane and Noam working around that area of
the code)

(make-network-process  :name "nc-connect"
                                   :family 'local
                                   :remote "/tmp/foo)
where /tmp/foo is a socket in /tmp.

The error thrown doesn't say anything useful, backtrace indicates it
got nil where it expected a string. 

The same call works in 26.1 -- and worked on Emacs built from head
until I updated yesterday evening.

-- 
Id: kg:/m/0285kf1 

-- 
Id: kg:/m/0285kf1