[snappy] ui: fix, don't go to next when in last of the list

[Luis de Bethencourt <luisbg src gnome org>]

commit a16ce014054c05f386be0a4a1713e0cf6a476fbe
Author: Luis de Bethencourt <luis debethencourt com>
Date:   Fri May 4 11:07:44 2012 +0100

    ui: fix, don't go to next when in last of the list

 src/user_interface.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)
---
diff --git a/src/user_interface.c b/src/user_interface.c
index 6a0ff6a..6382b5b 100644
--- a/src/user_interface.c
+++ b/src/user_interface.c
@@ -1051,11 +1051,13 @@ interface_play_next (UserInterface * ui)
 
   next = g_list_find (ui->uri_list, ui->engine->uri);
   next = g_list_next (next);
-  next_uri = next->data;
+  if (next != NULL) {
+    next_uri = next->data;
 
-  engine_open_uri (ui->engine, next_uri);
-  interface_load_uri (ui, next_uri);
-  engine_play (ui->engine);
+    engine_open_uri (ui->engine, next_uri);
+    interface_load_uri (ui, next_uri);
+    engine_play (ui->engine);
+  }
 }
 
 void