DiscoverObject: Ensure we actually quit in quitWhenIdle
For reasons not entirely clear, we may enter quitWhenIdle(), allow the QCloseEvent in the eventFilter, and then just not close.
This seems to happen if you quickly close Discover when opening it, during the brief period where the UI appears to hang.
reconsiderQuit() users a timer to quit (when we're still busy and showing SNI after closing), and it seems sensible to do the same here.
Edited by Nate Graham