Fetching inaccesible db can cause irresponsive ui and other issues

UI is not responsive when trying to connect stopped DB, some independent actions (like connection other running databases is blocked as well). When rebuild configuration is trigged, ui is completely frozen. Screencast http://www.screencast.com/t/wzUeHm7R4

Expected state:
1. Connection try should be shorter
2. Stopping fetching job should work
3. Independent databases should be always accesssible
4. IDE should not be freezing or forbidden action should be disabled