Merge pull request #27371 from andyzheng0831/network-plugin

Automatic merge from submit-queue

Revert "Revert "GCI: add support for network plugin""

PR #27027 added the network plugin support in GCI config, but later a bug in the network plugin broke e2e tests (see issue #27118). The bug was fixed by #27141 and we have been repeatedly run the serial e2e tests more than 10 times to verify the fix. Now it should be safe to put the GCI network plugin support back.

We will first merge in the master branch and monitor the Jenkins serial tests for a while and then cherry-pick it into release-1.3 branch.

hack/verify-flags/exceptions.txt

@@ -14,7 +14,9 @@ cluster/gce/configure-vm.sh:  cloud_config: ${CLOUD_CONFIG}
 cluster/gce/configure-vm.sh:  env-to-grains "runtime_config"
 cluster/gce/configure-vm.sh:  kubelet_api_servers: '${KUBELET_APISERVER}'
 cluster/gce/coreos/helper.sh:# cloud_config yaml file should be passed
+cluster/gce/gci/configure-helper.sh:      reconcile_cidr="false"
 cluster/gce/gci/configure-helper.sh:  local api_servers="--master=https://${KUBERNETES_MASTER_NAME}"
+cluster/gce/gci/configure-helper.sh:  local reconcile_cidr="true"
 cluster/gce/gci/configure-helper.sh:  sed -i -e "s@{{pillar\['allow_privileged'\]}}@true@g" "${src_file}"
 cluster/gce/trusty/configure-helper.sh:  sed -i -e "s@{{pillar\['allow_privileged'\]}}@true@g" "${src_file}"
 cluster/gce/util.sh:    local node_ip=$(gcloud compute instances describe --project "${PROJECT}" --zone "${ZONE}" \