CollectionGraphNode.RemoveElement doesn't work if ownedcollection is an array

[mortb]

RemoveElement won't work if the collection is an array

    private void RemoveElement(IChangeTracker changeTracker, object dbItem, object dbCollection)
    {
        dbCollection.GetType().GetMethod("Remove").Invoke(dbCollection, new[] { dbItem });
        changeTracker.AttachRequiredNavigationProperties(dbItem, dbItem);

        if (_isOwned)
        {
            changeTracker.RemoveItem(dbItem);
        }
    }

Well this may be a bit uncommon, but I mocked the database using
https://effort.codeplex.com/ I attached nested collections to my entities as arrays.
When removing child objects in the arrays and calling UpdateGraph with ownedcollection the above code fails as there is no Remove method on the Array class. It just threw a "nullref" excpetion wich was a bit unspecific.NotSupportedExcpeiton for removing items in arrays would have been better :)

The reason I got this far is that there is support for arrays in AttributeGraphBuilder. I think it would also throw if I'd added an object as this does GetMetod("Add")