Debugger: Silence warning on empty debugger settings in legitim cases

Change-Id: Ibaa830f615a3d739a198a9550cd955dc9151c009
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Fix generic highlighter autotest

Change-Id: I35994a8c29374edfeb8a230af10c2a3277232f22
Reviewed-by: Christian Stenger <christian.stenger@digia.com>
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>