explicit kubelet config key in Node.Spec.ConfigSource.ConfigMap

This makes the Kubelet config key in the ConfigMap an explicit part of
the API, so we can stop using magic key names.

As part of this change, we are retiring ConfigMapRef for ConfigMap.

test/integration/apiserver/print_test.go

@@ -50,7 +50,6 @@ var kindWhiteList = sets.NewString(
 	"ExportOptions",
 	"GetOptions",
 	"ListOptions",
-	"NodeConfigSource",
 	"NodeProxyOptions",
 	"PodAttachOptions",
 	"PodExecOptions",

test/integration/auth/node_test.go

@@ -286,12 +286,13 @@ func TestNodeAuthorizer(t *testing.T) {
 				return err
 			}
 			node2.Spec.ConfigSource = &api.NodeConfigSource{
-				ConfigMapRef: &api.ObjectReference{
+				ConfigMap: &api.ConfigMapNodeConfigSource{
 					Namespace: "ns",
 					Name:      "myconfigmapconfigsource",
 					// validation just requires UID to be non-empty and it isn't necessary for GET,
 					// so we just use a bogus one for the test
-					UID: "uid",
+					UID:              "uid",
+					KubeletConfigKey: "kubelet",
 				},
 			}
 			_, err = client.Core().Nodes().Update(node2)

test/integration/etcd/etcd_storage_path_test.go

@@ -437,7 +437,6 @@ var ephemeralWhiteList = createEphemeralWhiteList(
 	gvk("", "v1", "RangeAllocation"),     // stored in various places in etcd but cannot be directly created
 	gvk("", "v1", "ComponentStatus"),     // status info not stored in etcd
 	gvk("", "v1", "SerializedReference"), // used for serilization, not stored in etcd
-	gvk("", "v1", "NodeConfigSource"),    // subfield of node.spec, but shouldn't be directly created
 	gvk("", "v1", "PodStatusResult"),     // wrapper object not stored in etcd
 	// --