WebStorm 8 - Intellisense doesn't work with dependency injection

I'm trying out the intellisense in WebStorm 8 and it does work. I can create HTML and the ng-controller finds the controller correctly.

However, in this code:

var testModule = angular.module("test", []);

testModule.service("testService", function() {
   this.foo = 4; 
});

testModule.controller("testController", function(testService) {
    
});

When putting the cursor on the injected testService WebStorm says that it can't navigate to declaration. It also means, that if I write in the controller body, testService. I don't get any autocomplete.
Am I doing something wrong? Is this functionality supposed to be working?