GCE: respect static-ip assignment via update

[bprashanth]

Currently if you create an ingress then take its static-ip and assign the annotation, the controller is not smart enough to not delete the IP. To make this work:

1. Gate Static IP cleanup on a call to getEffectiveIP(): https://github.com/kubernetes/ingress/blob/master/controllers/gce/loadbalancers/loadbalancers.go#L828 (just like we do here https://github.com/kubernetes/ingress/blob/master/controllers/gce/loadbalancers/loadbalancers.go#L548)
2. Pipe the runtimeInfo into GC, instead of just the name (https://github.com/kubernetes/ingress/blob/master/controllers/gce/controller/controller.go#L324, https://github.com/kubernetes/ingress/blob/master/controllers/gce/controller/controller.go#L299)
3. Store the updated runtimeInfo in the L7 struct (), before calling delete()

This way the call to getEffectiveIP will observe the annotation value right before deleting the IP

[bowei]

This issue was moved to kubernetes/ingress-gce#26