debugger: remove unused DebuggerPlugin::stateChanged(int) signal

src/plugins/debugger/debuggerplugin.cpp

@@ -2303,9 +2303,6 @@ void DebuggerPluginPrivate::updateState(DebuggerEngine *engine)
         || m_state == DebuggerFinished
         || m_state == InferiorUnrunnable;
     setBusyCursor(!notbusy);
-
-    // FIXME: for QML only?
-    emit m_plugin->stateChanged(m_state);
 }
 
 void DebuggerPluginPrivate::resetLocation()

src/plugins/debugger/debuggerplugin.h

@@ -95,9 +95,6 @@ public slots:
     // void runTest(const QString &fileName);
     void showMessage(const QString &msg, int channel, int timeout = -1);
 
-signals:
-    void stateChanged(int);
-
 private:
     friend class Internal::DebuggerEngine;
     friend class Internal::DebuggerListener;