filtering changes the order of the DOM elements

If I apply a filter a list and take it away, DOM elements are inserted in a seemingly random order. This might be expected or even intentional, and I'm not sure if it's ember-collection's problem, but just wanted to point it out.

So if I have these items:

``` js
let items = [
{name: "Item 1"},
{name: "Item 2"},
{name: "Item 3"},
{name: "Item 4"},
{name: "Item 5"},
...
{name: "Item 10000"},
]
```

and

``` hbs

I get the HTML:

``` html

```

So far so good.

But if I apply a filter to `items` (lets say so `items` is only even number items) the HTML becomes something like this (note the random order)

``` html

The positions of the elements remains accurate (with absolute positioning), so the UI looks right.

The only use case for me right now is that I'm using `:nth-child(odd)` to give alternating row colors, and the random DOM ordering breaks that.

`:nth-child(odd)` CSS _also_ breaks with just regular scrolling because as new DOM elements are inserted, if the height of the parent can display an odd number of elements `n`, every `n` elements, there is a duplication. But this is less my concern than the random ordering on filter.

Here's a sample app to demonstrate: https://github.com/mehulkar/ember-collection-example