[mutter] egl: Fail first config choosing when no results

[Florian Müllner <fmuellner src gnome org>]

commit 7a41483ea066d9654c2eb3104cda27439ad4ca05
Author: Jonas Ådahl <jadahl gmail com>
Date:   Fri Feb 23 23:51:58 2018 +0800

    egl: Fail first config choosing when no results
    
    If there was no matching config, fail to find the first one.
    
    https://gitlab.gnome.org/GNOME/mutter/issues/2

 src/backends/meta-egl.c | 8 ++++++++
 1 file changed, 8 insertions(+)
---
diff --git a/src/backends/meta-egl.c b/src/backends/meta-egl.c
index d9c7b24d1..775863f88 100644
--- a/src/backends/meta-egl.c
+++ b/src/backends/meta-egl.c
@@ -299,6 +299,14 @@ meta_egl_choose_first_config (MetaEgl       *egl,
       return FALSE;
     }
 
+  if (num_matches == 0)
+    {
+      g_free (configs);
+      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                   "No matching EGLConfig found");
+      return FALSE;
+    }
+
   /*
    * We don't have any preference specified yet, so lets choose the first one.
    */