All commands must declare Unstructured or Internal

Callers must take a dependency on one or the other set of conversions
and default client behavior. Future changes may add a Versioned() type,
but this is an accurate reflection of current code state.

pkg/kubectl/cmd/drain.go

@@ -237,6 +237,7 @@ func (o *DrainOptions) SetupDrain(cmd *cobra.Command, args []string) error {
 	}
 
 	builder := o.Factory.NewBuilder().
+		Internal().
 		NamespaceParam(cmdNamespace).DefaultNamespace().
 		ResourceNames("nodes", args...).
 		SingleResourceType().