HTTP Abort Routing Rule does not work as expected

[sakows]

To Reproduce, run in GCP Kubernetes cluster version 1.8.4 with alpha feature enabled:

kubectl apply -f istio-0.4.0/install/kubernetes/istio.yaml
kubectl apply -f nginmesh-0.4.0/install/kubernetes/istio-initializer.yaml
kubectl apply -f istio-0.4.0/samples/bookinfo/kube/bookinfo.yaml
istioctl create -f nginmesh-0.4.0/samples/kubernetes/addons/route-rule-http-abort.yaml
Make few requests to sample application: http://GATEWAY_URL/productpage

Expected: According to rule, based on percent defined under httpFault section in routing configuration file, client requests should get "400 Bad Request" response code for Reviews V3 service proportionally.

Result: Client gets "503 Service Unavailable" response code after rule applied.

HTTP Abort Routing Rule documentation:
https://istio.io/docs/reference/config/traffic-rules/routing-rules.html#abort

HTTP Abort Routing Rule file:
route-rule-http-abort.yaml