Autocomplete control is retaining the dropdown values


I added a autocomplete control. When I select a value and then I go to another control, and then I return to the autocomplete to remove the value, the popup still shows the last items. Is like this is being cache, in spite of the data collection be empty.

This also happens in the demo:

Choose the 4th control ( AutoComplete with custom filtering), at the beginning is empty, but after you select a value, and then you remove it, then you will see that next time you enter again, the last dropdown selection will show.

Any idea how to prevent showing the last drop items when the collection is empty and the control value is empty.