Overall Test Status gadget based in JQL instead of using a filter

The Overall Test Status gadget shows a pie chart that depends on the filter you choose, not a JQL string.
This has some pros and cons. The pro is that you can control who can see the gadget. The con is that you have to update the filter every time you want to change the gadget.

The idea is to let the user enter a JQL string when they set up the gadget, so it's easier for them to use.