Debugger: split editor related code off watchutils.{h,cpp}

This is now in sourceutils.{h,cpp} to make watchutils.{h,cpp}
better acessible to the debugger auto-tests.

Change-Id: Ie87e715bc7018ca190a460c37dfd19bc897059f0
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

src/plugins/debugger/debuggerplugin.cpp

@@ -62,6 +62,7 @@
 #include "localsandexpressionswindow.h"
 #include "loadcoredialog.h"
 #include "hostutils.h"
+#include "sourceutils.h"
 
 #include "snapshothandler.h"
 #include "threadshandler.h"