CLOUDSTACK-5098: UI > VMware > during zone creation, after addVmwareDc succeeds, if addClsuter fails (e.g. because of wrong input value), zone detail page will show wrong button ("Add Vmware Datacenter") since listVmwareDcs is only called when a zone has a VMware cluster.
To resolve this specific use case, change UI to use listApis instead of listClusters to determine whether to call listVmwareDcs.