Weird case where a setter on a binding is not being fired when binding to an object, but does fire when bound to one of its properties.

gistfile1.txt

Fires the setter:
      "sampleComponent": {
            "prototype": "ui/sample-component.reel",
            "properties": {
                "element": {"#": "sampleComponent"}
            },
            "bindings": {
                "contentController": {"<-": "@randomItems.content"}
            }
        },

Does not fire the setter:
      "sampleComponent": {
            "prototype": "ui/sample-component.reel",
            "properties": {
                "element": {"#": "sampleComponent"}
            },
            "bindings": {
                "contentController": {"<-": "@randomItems"}
            }
        },

Here's the serialization code for randome items:
        "randomItems": {
            "prototype": "montage/ui/controller/array-controller",
            "properties": {
                "selectObjectsOnAddition": true,
                "automaticallyOrganizeObjects": true,
                "content": [
                    {
                        "id": "ID003",
                        "order": "1",
                        "title": "Sample 1"
                    },
                    {
                        "id": "ID002",
                        "order": "2",
                        "title": "random text"
                    }
                ]
            }
        },

getter/setter for the contentController
    contentController: {
        get : function () {
            return this._contentController;
        },
        set : function(value) {
            if (this._contentController != value) {
                this._contentController = value;
            }
        }
    },