[grilo-plugins] local-metadata: Fix segmentation fault

[Juan A. Suarez Romero <jasuarez src gnome org>]

commit 0494be4ec2e1b7a202e9f53b6c5780eff771b19c
Author: Juan A. Suarez Romero <jasuarez igalia com>
Date:   Mon Sep 3 10:39:18 2012 +0000

    local-metadata: Fix segmentation fault
    
    Check if there is any scheme returned.

 src/local-metadata/grl-local-metadata.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/local-metadata/grl-local-metadata.c b/src/local-metadata/grl-local-metadata.c
index c6b9a3e..7faf879 100644
--- a/src/local-metadata/grl-local-metadata.c
+++ b/src/local-metadata/grl-local-metadata.c
@@ -789,6 +789,10 @@ is_supported_scheme (const char *scheme)
   vfs = g_vfs_get_default ();
   schemes = g_vfs_get_supported_uri_schemes (vfs);
 
+  if (!schemes) {
+    return FALSE;
+  }
+
   for (i = 0; schemes[i] != NULL; i++) {
     if (g_str_equal (schemes[i], scheme))
       return TRUE;