virsh: Don't clear old connection if 'connect $uri' fails
virsh: Don't clear old connection if 'connect $uri' fails

    virsh # list --all
     Id    Name                           State
    ----------------------------------------------------
     1     test                           running

    virsh # connect frob
    error: Failed to connect to the hypervisor
    error: no connection driver available for frob

    virsh # list --all
    error: failed to connect to the hypervisor
    error: no valid connection
    error: no connection driver available for frob

Seems sensible IMO to just not clear out the old connection state
until the new virConnectOpen succeeds.

https://bugzilla.redhat.com/show_bug.cgi?id=829160

VenkatDatta/libvirt,crobinso/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,libvirt/libvirt,libvirt/libvirt,VenkatDatta/libvirt,taget/libvirt,andreabolognani/libvirt,jfehlig/libvirt,nertpinx/libvirt,zippy2/libvirt,andreabolognani/libvirt,jfehlig/libvirt,datto/libvirt,datto/libvirt,jardasgit/libvirt,taget/libvirt,jfehlig/libvirt,eskultety/libvirt,eskultety/libvirt,nertpinx/libvirt,crobinso/libvirt,eskultety/libvirt,libvirt/libvirt,taget/libvirt,jardasgit/libvirt,olafhering/libvirt,VenkatDatta/libvirt,taget/libvirt,datto/libvirt,crobinso/libvirt,eskultety/libvirt,nertpinx/libvirt,olafhering/libvirt,andreabolognani/libvirt,zippy2/libvirt,jfehlig/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,crobinso/libvirt,zippy2/libvirt,olafhering/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,zippy2/libvirt,libvirt/libvirt,datto/libvirt,jardasgit/libvirt,eskultety/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,nertpinx/libvirt,taget/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,datto/libvirt,olafhering/libvirt,nertpinx/libvirt,fabianfreyer/libvirt