QFutureCallOutEvent: remove unused pseudo-copy-ctor

This constructor was used in the previous implementation of
clone(). The current implementation uses the compiler-generated
copy-constructor.

Change-Id: Ibae163653e43ceb2b07872b496cd004e50b1e625
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/thread/qfutureinterface_p.h

@@ -103,18 +103,6 @@ public:
     int index1;
     int index2;
     QString text;
-
-private:
-    QFutureCallOutEvent(CallOutType callOutType,
-                        int index1,
-                        int index2,
-                        const QString &text)
-        : QEvent(QEvent::FutureCallOut),
-          callOutType(callOutType),
-          index1(index1),
-          index2(index2),
-          text(text)
-    { }
 };
 
 class Q_CORE_EXPORT QFutureCallOutInterface