gtk3: fix display changed signal emissions

vcl/generic/app/gendisp.cxx

@@ -73,6 +73,12 @@ void SalGenericDisplay::deregisterFrame( SalFrame* pFrame )
     m_aFrames.remove( pFrame );
 }
 
+void SalGenericDisplay::emitDisplayChanged()
+{
+    if( !m_aFrames.empty() )
+        m_aFrames.front()->CallCallback( SALEVENT_DISPLAYCHANGED, 0 );
+}
+
 bool SalGenericDisplay::DispatchInternalEvent()
 {
     void* pData = NULL;
@@ -152,4 +158,6 @@ bool SalGenericDisplay::HasUserEvents() const
     return bRet;
 }
 
+
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

vcl/inc/generic/gendisp.hxx

@@ -68,6 +68,7 @@ public:
 
     virtual void registerFrame( SalFrame* pFrame );
     virtual void deregisterFrame( SalFrame* pFrame );
+            void emitDisplayChanged();
 
     // Event handling
     virtual void PostUserEvent() = 0;

vcl/unx/generic/app/randrwrapper.cxx

@@ -350,8 +350,8 @@ int SalDisplay::processRandREvent( XEvent* pEvent )
                     #endif
                 }
             }
-            if( bNotify && ! m_aFrames.empty() )
-                m_aFrames.front()->CallCallback( SALEVENT_DISPLAYCHANGED, 0 );
+            if( bNotify )
+                emitDisplayChanged();
         }
     }
     #else

vcl/unx/gtk/app/gtkdata.cxx

@@ -204,24 +204,14 @@ GdkFilterReturn GtkSalDisplay::filterGdkEvent( GdkXEvent* sys_event,
 
 void GtkSalDisplay::screenSizeChanged( GdkScreen* pScreen )
 {
-#if !GTK_CHECK_VERSION(3,0,0)
     if (pScreen)
-        m_aFrames.front()->CallCallback( SALEVENT_DISPLAYCHANGED, 0 );
-#else
-    (void)pScreen;
-#warning FIXME: implement screenSizeChanged ...
-#endif
+        emitDisplayChanged();
 }
 
 void GtkSalDisplay::monitorsChanged( GdkScreen* pScreen )
 {
-#if !GTK_CHECK_VERSION(3,0,0)
     if (pScreen)
-        m_aFrames.front()->CallCallback( SALEVENT_DISPLAYCHANGED, 0 );
-#else
-    (void)pScreen;
-#warning FIXME: implement monitorsChanged for gtk3
-#endif
+        emitDisplayChanged();
 }
 
 extern "C"