Cleanup some code leftovers from a previous refactor (kubernetes-sigs#1118)

Author: zcahana

pkg/predicate/predicate.go

@@ -122,21 +122,14 @@ type ResourceVersionChangedPredicate struct {
 // Update implements default UpdateEvent filter for validating resource version change
 func (ResourceVersionChangedPredicate) Update(e event.UpdateEvent) bool {
 	if e.ObjectOld == nil {
-		log.Error(nil, "UpdateEvent has no old metadata", "event", e)
-		return false
-	}
-	if e.ObjectOld == nil {
-		log.Error(nil, "GenericEvent has no old runtime object to update", "event", e)
+		log.Error(nil, "Update event has no old object to update", "event", e)
 		return false
 	}
 	if e.ObjectNew == nil {
-		log.Error(nil, "GenericEvent has no new runtime object for update", "event", e)
-		return false
-	}
-	if e.ObjectNew == nil {
-		log.Error(nil, "UpdateEvent has no new metadata", "event", e)
+		log.Error(nil, "Update event has no new object to update", "event", e)
 		return false
 	}
+
 	return e.ObjectNew.GetResourceVersion() != e.ObjectOld.GetResourceVersion()
 }
 
@@ -163,21 +156,14 @@ type GenerationChangedPredicate struct {
 // Update implements default UpdateEvent filter for validating generation change
 func (GenerationChangedPredicate) Update(e event.UpdateEvent) bool {
 	if e.ObjectOld == nil {
-		log.Error(nil, "Update event has no old metadata", "event", e)
-		return false
-	}
-	if e.ObjectOld == nil {
-		log.Error(nil, "Update event has no old runtime object to update", "event", e)
+		log.Error(nil, "Update event has no old object to update", "event", e)
 		return false
 	}
 	if e.ObjectNew == nil {
-		log.Error(nil, "Update event has no new runtime object for update", "event", e)
-		return false
-	}
-	if e.ObjectNew == nil {
-		log.Error(nil, "Update event has no new metadata", "event", e)
+		log.Error(nil, "Update event has no new object for update", "event", e)
 		return false
 	}
+
 	return e.ObjectNew.GetGeneration() != e.ObjectOld.GetGeneration()
 }