
This is reproducable in the Sample Browser (QuickStart 10)
1. Start typing (e.g. "Inc" for Increment) and then request auto completion.
2. Select one item (e.g. "Increment").
3. Undo
While it's correct that the text displays "Inc" again, I think it's not correct that the text is selected. The cursor should be after the typed text and no selection at all. The respective text hasn't been selected before so there's no reason it should be selected now.