Fix Qt < 5.3 compat. issue in DebugOutput; AppDebugMessageHandler: Filter out verbose QPainter warnings on Linux Qt < 5.3; Do not return any instance if disabled entirely; Fix style sheet for simulator radio background.
Fix Qt < 5.3 compat. issue in DebugOutput; AppDebugMessageHandler: Filter out verbose QPainter warnings on Linux Qt < 5.3; Do not return any instance if disabled entirely; Fix style sheet for simulator radio background.