Bug fix for [ 1059381 ] Mouse wheel does not work in listctrl with gtk2

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@31363 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/listctrl.cpp

@@ -2874,6 +2874,15 @@ void wxListMainWindow::OnMouse( wxMouseEvent &event )
     if ( GetParent()->GetEventHandler()->ProcessEvent( event) )
         return;
 
+#if wxUSE_MOUSEWHEEL
+    if (event.GetEventType() == wxEVT_MOUSEWHEEL)
+    {
+        // let the base handle mouse wheel events.
+        event.Skip();
+        return;
+    }
+#endif
+    
     if ( !HasCurrent() || IsEmpty() )
         return;