Quick filter on plan board should show issues with sub-tasks that match query

If a story has a sub-task that matches a quick filter that story will appear on the work board. If you switch to the story board though and use the quick filter the same story won't appear. This is because sub-tasks don't appear on the plan board.

Even though sub-tasks shouldn't appear on the plan board it should be possible to view the parents of those tasks if any of the sub-tasks are valid under a quick filter.