Forked from GoogleCloudPlatform/k8s-multicluster-ingress#131

ingress-gce controller is configuring the whole load balancer including creating url map, target proxy, etc for multicluster ingresses.
This is a regression. It should only manage instance groups.

Thanks to @MrHohn for finding the problem.
@nicksardo is working on a fix and I am going to send a PR to update the ingress-gce tests to catch this early.

Filing this issue to track

cc @csbell @G-Harmon @bowei