kubelet e2e: enforce that image prepulling must finish before the test

The image prepulling pod calls docker directly to pull images. If the pod
hasn't finished before running the resource usage tracking test, there'd be a
cpu spike in docker. We'd rather wait and fail if this is the case, before
running the test.

test/e2e/resize_nodes.go

@@ -424,9 +424,10 @@ var _ = framework.KubeDescribe("Nodes [Disruptive]", func() {
 			// Many e2e tests assume that the cluster is fully healthy before they start.  Wait until
 			// the cluster is restored to health.
 			By("waiting for system pods to successfully restart")
-
 			err := framework.WaitForPodsRunningReady(c, api.NamespaceSystem, systemPodsNo, framework.PodReadyBeforeTimeout, ignoreLabels)
 			Expect(err).NotTo(HaveOccurred())
+			By("waiting for image prepulling pods to complete")
+			framework.WaitForPodsSuccess(c, api.NamespaceSystem, framework.ImagePullerLabels, imagePrePullingTimeout)
 		})
 
 		It("should be able to delete nodes", func() {