WIP: Sign the just-built signer image

That should ~guarantee the image is unique, and doesn't have
some strange inaccessible Image.dockerImageReference.

Signed-off-by: Miloslav Trmač <[email protected]>

Author: mtrmac

test/extended/images/signatures.go

@@ -11,7 +11,6 @@ import (
 	e2e "k8s.io/kubernetes/test/e2e/framework"
 
 	exutil "github.com/openshift/origin/test/extended/util"
-	"github.com/openshift/origin/test/extended/util/image"
 )
 
 var _ = g.Describe("[sig-imageregistry][Serial][Suite:openshift/registry/serial] Image signature workflow", func() {
@@ -106,7 +105,7 @@ var _ = g.Describe("[sig-imageregistry][Serial][Suite:openshift/registry/serial]
 			"--src-cert-dir=/run/secrets/kubernetes.io/serviceaccount",
 			"--dest-cert-dir=/run/secrets/kubernetes.io/serviceaccount",
 
-			"docker://" + image.ShellImage(),
+			"docker://" + signerImage,
 			"docker://" + signedImage,
 		}, " "))
 		fmt.Fprintf(g.GinkgoWriter, "output: %s\n", out)