Add Job.spec.completionMode and Job.status.completedIndexes

And IndexedJob feature gate, disabled by default.
Update JobDescriber

pkg/apis/batch/fuzzer/fuzzer.go

@@ -18,7 +18,6 @@ package fuzzer
 
 import (
 	fuzz "github.com/google/gofuzz"
-
 	runtimeserializer "k8s.io/apimachinery/pkg/runtime/serializer"
 	"k8s.io/kubernetes/pkg/apis/batch"
 )
@@ -53,6 +52,11 @@ var Funcs = func(codecs runtimeserializer.CodecFactory) []interface{} {
 			} else {
 				j.ManualSelector = nil
 			}
+			if c.Rand.Int31()%2 == 0 {
+				j.CompletionMode = batch.NonIndexedCompletion
+			} else {
+				j.CompletionMode = batch.IndexedCompletion
+			}
 		},
 		func(sj *batch.CronJobSpec, c fuzz.Continue) {
 			c.FuzzNoCustom(sj)