Description of problem:
Observed a panic: "invalid memory address or nil pointer dereference" when creating ingress with malformed file  

Version-Release number of selected component (if applicable):
openshift v3.5.0.19+199197c
kubernetes v1.5.2+43a9be4
etcd 3.1.0

router image: ose-haproxy-router  v3.5.0.19    525568cc07b5

How reproducible:
always

Steps to Reproduce:
1. enable ingress
# oc env dc/router ROUTER_ENABLE_INGRESS=true
2. create ingress from malformed file (host without http section) :
# oc create -f error-ingress.yaml -n u2p2
ingress "test" created
# cat error-ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: test
spec:
  rules:
  - host: foo.bar.com


Actual results:
The ingress is created but error logs in haproxy router pod:
E0213 09:48:24.357266       1 runtime.go:64] Observed a panic: "invalid memory address or nil pointer dereference" (runtime error: invalid memory address or nil pointer dereference)
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/util/runtime/runtime.go:70
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/util/runtime/runtime.go:63
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/util/runtime/runtime.go:49
/usr/lib/golang/src/runtime/asm_amd64.s:479
/usr/lib/golang/src/runtime/panic.go:458
/usr/lib/golang/src/runtime/panic.go:62
/usr/lib/golang/src/runtime/sigpanic_unix.go:24
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/pkg/router/controller/ingress.go:443
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/pkg/router/controller/ingress.go:244
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/pkg/router/controller/ingress.go:209
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/pkg/router/controller/ingress.go:129
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/pkg/router/controller/controller.go:239
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/pkg/router/controller/controller.go:81
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/util/wait/wait.go:96
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/util/wait/wait.go:97
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/util/wait/wait.go:52
/builddir/build/BUILD/atomic-openshift-git-0.199197c/_output/local/go/src/github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/util/wait/wait.go:43
/usr/lib/golang/src/runtime/asm_amd64.s:2086

Expected results:
should not show panic error

Additional info:
the ingress is created and you can get ingress:
[root@host-8-175-173 ~]# oc get ingress -n u2p2 -o yaml
apiVersion: v1
items:
- apiVersion: extensions/v1beta1
  kind: Ingress
  metadata:
    creationTimestamp: 2017-02-13T09:48:24Z
    generation: 1
    name: test
    namespace: u2p2
    resourceVersion: "8502"
    selfLink: /apis/extensions/v1beta1/namespaces/u2p2/ingresses/test
    uid: 8fbfb046-f1d1-11e6-926a-fa163e172ae0
  spec:
    rules:
    - host: foo.bar.com
  status:
    loadBalancer: {}
kind: List
metadata: {}
resourceVersion: ""
selfLink: ""
[root@host-8-175-173 ~]#