Observer displayed with ngFor nested in ngIf does not display the right value

```
[x ] bug report
```

http://plnkr.co/edit/glqjC6CFQDzSn1pJHHgF?p=preview

In this plnkr, the same observer is used to display a list via 2 ngFor. The ngFor nested in the ngIf is always out of sync with the one outside of the ngIf. The 2 list should display the same thing at the same moment, it is the same object.