Description of problem:
there is no exception handling for none pid vms.

/usr/share/vdsm/supervdsmServer

    def _getPid(self):
        pid = '0'
        try:
            vmName = self.conf['vmName'].encode('utf-8')
            pid = supervdsm.getProxy().getVmPid(vmName)
        except Exception:
            pass
        return pid


Version-Release number of selected component (if applicable):
vdsm-4.14.11-1.el6ev.x86_64

How reproducible:
many side affects

Steps to Reproduce:
1.
2.
3.

Actual results:
the process of the vm exist but no pid file.

Expected results:
shutdown vm in case no pid exist.

Additional info: