Re: [libvirt] [libvirt-glib] config: Fix typo preventing clock removal from a domain

Commit 1c8ce29 added a way to unset a GVirConfigDomainClock set on a GVirConfigDomain by calling gvir_config_domain_set_clock() with a NULL argument. However, a typo in a g_return_if_fail precondition prevents this code from ever being called: g_return_if_fail(clock != NULL) is used while it should have been g_return_if_fail(clock == NULL) as in all other preconditions in 1c8ce29.