evince does not open with broadway backend

[Vaclav Petras]

On Lubuntu 15.04, when trying to open Evince with GTK+ Broadway backend, Evince reports incomplete errors and then ends.

In first terminal:

$ broadwayd -a 127.0.0.1 -p 8889 :2
Listening on /run/user/1000/broadway3.socket

In second terminal:

$ GDK_BACKEND=broadway BROADWAY_DISPLAY=:2 evince
Unable to init server: Could not connect: Permission denied
Cannot parse arguments: Cannot open display:

(There is nothing more in the output, program ends.)

gtk3-demo or gitg have GUI in a browser as expected.

Not sure if related or if it is perhaps expected, but I cannot see the socket file (with sudo or without):

$ ls /run/user/1000/broadway3.socket
ls: cannot access /run/user/1000/broadway3.socket: No such file or directory

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: libgtk-3-0 3.14.13-0ubuntu1
ProcVersionSignature: Ubuntu 3.19.0-21.21-generic 3.19.8
Uname: Linux 3.19.0-21-generic x86_64
ApportVersion: 2.17.2-0ubuntu1.1
Architecture: amd64
CurrentDesktop: LXDE
Date: Wed Jul 8 17:13:25 2015
InstallationDate: Installed on 2015-02-09 (149 days ago)
InstallationMedia: Lubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1)
SourcePackage: gtk+3.0
UpgradeStatus: Upgraded to vivid on 2015-05-30 (38 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Max Chao (yochaos)]

It was fixed in evince 3.18.2. Tested with xenial.