cleanup some code (#4989)

Automatically submitted.

plugin/cache/dnssec.go

@@ -26,7 +26,7 @@ func isDNSSEC(r dns.RR) bool {
 // returned.
 func filterRRSlice(rrs []dns.RR, ttl uint32, do, dup bool) []dns.RR {
 	j := 0
-	rs := make([]dns.RR, len(rrs), len(rrs))
+	rs := make([]dns.RR, len(rrs))
 	for _, r := range rrs {
 		if !do && isDNSSEC(r) {
 			continue

plugin/clouddns/gcp.go

@@ -31,9 +31,7 @@ func (c gcpClient) listRRSets(ctx context.Context, projectName, hostedZoneName s
 	req := c.ResourceRecordSets.List(projectName, hostedZoneName)
 	var rs []*gcp.ResourceRecordSet
 	if err := req.Pages(ctx, func(page *gcp.ResourceRecordSetsListResponse) error {
-		for _, rr := range page.Rrsets {
-			rs = append(rs, rr)
-		}
+		rs = append(rs, page.Rrsets...)
 		return nil
 	}); err != nil {
 		return nil, err

plugin/kubernetes/namespace.go

@@ -6,10 +6,7 @@ package kubernetes
 // see namespaceExposed.
 func (k *Kubernetes) filteredNamespaceExists(namespace string) bool {
 	_, err := k.APIConn.GetNamespaceByName(namespace)
-	if err != nil {
-		return false
-	}
-	return true
+	return err == nil
 }
 
 // configuredNamespace returns true when the namespace is exposed through the plugin