[mutter/gnome-3-28] monitor-manager: fix output ids returned by GetResources

[Jonas Ådahl <jadahl src gnome org>]

commit 23c3f8bb18db499d196f1024732ef3234b44f59c
Author: Aleksandr Mezin <mezin alexander gmail com>
Date:   Sun Apr 8 01:40:30 2018 +0600

    monitor-manager: fix output ids returned by GetResources
    
    Output ID is set equal to 'i' later in the loop. But 'i' was never
    incremented, so all outputs were getting the same ID (equal to
    the number of CRTCs, because 'i' was reused from the previous loop).

 src/backends/meta-monitor-manager.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/backends/meta-monitor-manager.c b/src/backends/meta-monitor-manager.c
index 08603a7a5..e952e4f75 100644
--- a/src/backends/meta-monitor-manager.c
+++ b/src/backends/meta-monitor-manager.c
@@ -1032,7 +1032,7 @@ meta_monitor_manager_handle_get_resources (MetaDBusDisplayConfig *skeleton,
                              NULL /* properties */);
     }
 
-  for (l = combined_outputs; l; l = l->next)
+  for (l = combined_outputs, i = 0; l; l = l->next, i++)
     {
       MetaOutput *output = l->data;
       GVariantBuilder crtcs, modes, clones, properties;