[mutter] background: Fix monitor validation in get_texture()

[Florian Müllner <fmuellner src gnome org>]

commit 9be3e56b70d6b19d843cd4447559ba5191b36d94
Author: Florian Müllner <fmuellner gnome org>
Date:   Sat Sep 6 18:21:20 2014 +0200

    background: Fix monitor validation in get_texture()
    
    Monitor indexes should be in the range [0, n], not [-1, 0] :-)

 src/compositor/meta-background.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/compositor/meta-background.c b/src/compositor/meta-background.c
index cbcbdea..1fab45e 100644
--- a/src/compositor/meta-background.c
+++ b/src/compositor/meta-background.c
@@ -679,7 +679,7 @@ meta_background_get_texture (MetaBackground         *self,
 
   g_return_val_if_fail (META_IS_BACKGROUND (self), NULL);
   priv = self->priv;
-  g_return_val_if_fail (monitor_index <= 0 && monitor_index < priv->n_monitors, NULL);
+  g_return_val_if_fail (monitor_index >= 0 && monitor_index < priv->n_monitors, NULL);
 
   monitor = &priv->monitors[monitor_index];