Description of problem:
----------------------
sudo gdb ./virt-viewer
(gdb) run
Starting program: /usr/bin/virt-viewer 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

(virt-viewer:16393): GSpice-WARNING **: Warning no automount-inhibiting implementation available
[New Thread 0x7fffceffe700 (LWP 16400)]
[New Thread 0x7fffe06a9700 (LWP 16398)]
[New Thread 0x7fffe0eaa700 (LWP 16397)]

Program received signal SIGSEGV, Segmentation fault.
0x0000000000413290 in virt_viewer_align_monitors_linear ()

Version-Release number of selected component (if applicable):
-------------------------------------------------------------
Last virt-manager Github sources e5a0d1cbb8a4667d549d68e5b6c82dbd9f28b44f
Last virt-viewer Github sources aff6c79ae080db286e4cb853cdfa02f2da0d0398
Libvirt 1.2.20
Libvirt glib 1.0.2
Python libvirt 1.2.19
Qemu 2.4.0

Steps to Reproduce:
------------------
1. virt-manager
2. run a VM
3. virt-viewer

Additional info:
---------------
Ubuntu Server 15.04 3.19.0-30-generic