wxSystemSettings::GetMetric returns -1 if the metric is not supported

by the port.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@29554 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/settings.cpp

@@ -378,7 +378,7 @@ int wxSystemSettingsNative::GetMetric( wxSystemMetric index )
         case wxSYS_ICON_X:     return 32;
         case wxSYS_ICON_Y:     return 32;
         default:               
-            return 0;   // metric is unknown
+            return -1;   // metric is unknown
     }
 }