Description of problem:
Currently, virt-viewer in virt-viewer mode requires to specify --spice-ca-file and --spice-host-subject options. These are beneficial to require when connecting to insecure libvirt URI (remote uri with tcp transport or if we nanny the user, ext transport as well) but when connecting over unix, tls, ssh or libssh2 transports, these informations can be fetched in a secure way without need to bug the user about them.

spice-gtk accepts CA file currently as a file only but there is proposal for it to be able to accept it via file that seems simple enough to be accepted quite soon so I'm making this depend on that bug (bug 882329) so that we do this right(TM) from the beginning.

Version-Release number of selected component (if applicable):
virt-viewer-0.5.2-16.el6.x86_64

How reproducible:
always

Steps to Reproduce:
1. if not already set up this way
create spice keys/certificates and configure qemu.conf to enable spice_tls and point it to directory with certs/keys
2. create a domain that will require tls connection on spice main channel:
domain xml:
<?xml version="1.0"?>
<domain type="kvm">
  <name>tls-main</name>
  <memory>32768</memory>
  <os>
    <type arch="x86_64" machine="pc">hvm</type>
  </os>
  <devices>
    <graphics type="spice" autoport="yes" >
      <channel name="main" mode="secure" />
    </graphics>
    <video>
      <model type="qxl" vram="32768" heads="1"/>
    </video>
  </devices>
</domain>

create the ephemeral domain:
virsh [-c LIBVIRT_URI] create PATH_TO_XML

3. open the domain console using any transport but tcp (just qemu:///system is fine for example):
virt-viewer --spice-debug -c LIBVIRT_URI tls-main
  
Actual results:
virt-viewer doesn't connect and its output contains these lines:

(virt-viewer:24275): GSpice-DEBUG: spice-session.c:1617 Trying one socket
(virt-viewer:24275): GSpice-DEBUG: spice-session.c:1566 main-1:0: Socket pending
(virt-viewer:24275): GSpice-DEBUG: spice-session.c:1581 main-1:0: Finally connected
(virt-viewer:24275): GSpice-DEBUG: spice-channel.c:1160 main-1:0: channel type 1 id 0 num common caps 1 num caps 1
(virt-viewer:24275): GSpice-DEBUG: spice-channel.c:1182 main-1:0: Peer version: 2:2
(virt-viewer:24275): GSpice-DEBUG: spice-channel.c:1666 main-1:0: switching to tls
(virt-viewer:24275): GSpice-DEBUG: spice-channel.c:2040 main-1:0: channel has error, breaking loop
(virt-viewer:24275): GSpice-DEBUG: spice-channel.c:2255 main-1:0: Open coroutine starting 0x943fa0
(virt-viewer:24275): GSpice-DEBUG: spice-channel.c:2098 main-1:0: Started background coroutine 0x944028
(virt-viewer:24275): GSpice-DEBUG: spice-session.c:1604 Resolving host localhost 5901
(virt-viewer:24275): GSpice-DEBUG: spice-session.c:1617 Trying one socket
(virt-viewer:24275): GSpice-DEBUG: spice-session.c:1566 main-1:0: Socket pending
(virt-viewer:24275): GSpice-DEBUG: spice-session.c:1581 main-1:0: Finally connected
(virt-viewer:24275): GSpice-DEBUG: spice-channel.c:2148 main-1:0: CA file: /home/david/.spicec/spice_truststore.pem

note that ${HOME}/.spicec/spice_truststore.pem is fallback path when no CA file is given to spice-gtk


Expected results:
virt-viewer connects just fine

Additional info: