Steps to reproduce:

1. Monitor an item with the Gauge widget.
2. Make sure there is some data for the item. Make sure Gauge shows a value.
3. Clear the item's data (clear history and trends from another tab).
4. Wait for Gauge to refresh on it's own.

Result:
The data is not cleared. "No data" is overlaid the old value:

Expected:
Value is cleared, only "No data" is shown.