Adding Typescript module voids structure view

The structure view works great when I want to browse a collection of classes and their attributes in a typescript file. But when I enclose the classes in a module, the structure view is emptied. Am I missing something? Should I be filing a bug for this? This is on Webstorm 9.03.

As an example, this:

module Foo {
    class Bar {
        setValue(newValue) {
            var blah = "foobar baz";
        }
    }
}

yields this: