debugger: fix translation contexts

* add a few Q_OBJECT
* change DebuggerRunControl::tr() to DebuggerPlugin::tr()

Change-Id: I7ed973ea71b3492e91b45784595d9471587f72ea
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>

src/plugins/debugger/threadswindow.h

@@ -53,6 +53,8 @@ private:
 
 class ThreadsWindow : public BaseWindow
 {
+    Q_OBJECT
+
 public:
     ThreadsWindow();
 };