attempting to open a console on a VM with a broken/stopped/non-responsive guest agent doesn't work

[sjd78]

When I run a VM configured with a guest agent and it isn't accessible yet, the SSO logon rest call fails and no console is opened.

This VM is running but something is wrong with the guest agent (the Disk utilization card is also empty):

I first saw the problem when I started this VM and tried to open the console before the VM was "Running".

VM Portal version number: master + #956 (but it looks more like an SSO/guest agent issue that the VNC console)

oVirt version number: 4.3.1.2-0.0.master.20190220155021.git90ab3d9.el7

Browser and version: Chrome 72.0.3626.96 or FF 65

Steps to Reproduce (the first time I had the issue):

1. Have a VM with an enabled guest agent (qemu or ovirt)
2. While the VM is running make sure the console can be opened
3. Stop the VM
4. Start the VM and attempt to open the console before it is Up / Running
5. No console opens and the debug console shows a 400 error on the logon rest call
6. At some point in the future, after the VM is Up the console will start working (sometime connecting to the console via webadmin will kick it hard enough to start working)

Actual results: The console doesn't open and no user error is shown.

Expected results: The console opens so the BIOS and boot screens can be seen.

Additional info: The Utilization / Disks chart also misbehaves. My VM is CentOS 7 and is current qemu-guest-agent: