web-mode-indentation wrong

Question

Using web-mode and evil I get a really strange behaviour when pressing return after curly braces:

let StubMapsService = Ember.Service.extend({
    getMapElement(location) { (RET)
        }
});

let f = function(assert) { (RET)
    }

RET is set to "evil-ret".

When writing java-files the Indentation is correct after inserting }.

Also when I press C-c TAB in web-mode, so web-mode auto-indents the buffer, then everything looks correct:

let StubMapsService = Ember.Service.extend({
    getMapElement(location) {
    }
});

let f = function(assert) {
}

I searched for an hour for a solution. I tried changing c-indent-offset, setting web-mode-code-indent-offset, but nothing helped. Turning off electric-indent-mode I get no indentation after pressing RET. Any Idea what is going wrong?