Merge pull request #24798 from thockin/validation_pt8-1

Automatic merge from submit-queue

Make IsQualifiedName return error strings

Part of the larger validation PR, broken out for easier review and merge.

@lavalamp FYI, but I know you're swamped, too.

pkg/volume/plugins.go

@@ -272,7 +272,7 @@ func (pm *VolumePluginMgr) InitPlugins(plugins []VolumePlugin, host VolumeHost)
 	allErrs := []error{}
 	for _, plugin := range plugins {
 		name := plugin.Name()
-		if !validation.IsQualifiedName(name) {
+		if len(validation.IsQualifiedName(name)) != 0 {
 			allErrs = append(allErrs, fmt.Errorf("volume plugin has invalid name: %#v", plugin))
 			continue
 		}