Change in vdsm[master]: vmdevices: use default if no displayNetwork

[Code Review]

From Dan Kenigsberg :

Dan Kenigsberg has posted comments on this change.

Change subject: vmdevices: use default if no displayNetwork
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Patch Set 2: Code-Review-1

(2 comments)

https://gerrit.ovirt.org/#/c/75134/2/lib/vdsm/virt/vmdevices/graphics.py
File lib/vdsm/virt/vmdevices/graphics.py:

PS2, Line 67: guests_gateway_ip
this is an ancient sh*t that nobody is using (or at least should be using). Please don't duplicate it here - it's more than enough in _getNetworkIp.

If displayNetwork is not specified, we listen on everything ('0'). With any other value, the VM would not be migratable.

Line 235:         # the device is defaulted to the network name (i.e. northbound port).
Line 236:         device = (nets[network].get('iface', network)
Line 237:                   if network in nets else network)
Line 238:         ip, _, _, _ = net_api.ip_addrs_info(device)
Line 239:     # TODO: is this still an option with on-demand created networks?
I don't understand this TODO.
Line 240:     except (libvirt.libvirtError, KeyError, IndexError):
Line 241:         ip = config.get('addresses', 'guests_gateway_ip')
Line 242:     finally:
Line 243:         if ip == '':