Fix focus, defaultId, foregroundId logic

Fix focus, defaultId, foregroundId logic

[Bug/Feature]   Buggy focus logic. DefaultId, foregroundId does not work
                after implementing dynamic zone adding and removing.
[Cause]         N/A
[Solution]      Update focus after remove, pause and stop zone.
                DefaultId moved to dynamic config. ForegroundId removed
                from config.
[Verification]  Build, run tests, run daemon and check focus after
                adding, pausing, removing zones, switching zones.

Change-Id: I325e501242b747802da07b103ccba4c20891138e