[cheese] cheese-camera: Check return of linking effect

[Luciana Fujii Pontello <lufujii src gnome org>]

commit 6a5acbb27eb5d97175061430ac8abc907bb6852c
Author: Luciana Fujii Pontello <luciana fujii eti br>
Date:   Mon Jan 17 18:43:26 2011 -0200

    cheese-camera: Check return of linking effect
    
    Return if linking effect preview was not successful.

 libcheese/cheese-camera.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/libcheese/cheese-camera.c b/libcheese/cheese-camera.c
index da07e7d..6aed32e 100644
--- a/libcheese/cheese-camera.c
+++ b/libcheese/cheese-camera.c
@@ -874,6 +874,7 @@ cheese_camera_connect_effect_texture (CheeseCamera *camera, CheeseEffect *effect
 
 
   ok = gst_element_link_many (priv->effects_tee, control_valve, effect_filter, display_queue, display_element, NULL);
+  g_return_if_fail (ok);
 
   /* HACK: I don't understand GStreamer enough to know why this works. */
   gst_element_set_state (control_valve, GST_STATE_PLAYING);