[bijiben] share: Never return empty arguments

[Bastien Nocera <hadess src gnome org>]

commit c6ffb00e1cfecca5dc5390459fd35531b61251e8
Author: Bastien Nocera <hadess hadess net>
Date:   Thu Mar 14 15:15:16 2013 +0100

    share: Never return empty arguments
    
    This fixes xdg-email not working when the note is empty.
    
    xdg-email: text argument missing for --subject option
    Try 'xdg-email --help' for more information.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=695849

 src/bjb-share.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/bjb-share.c b/src/bjb-share.c
index ae169c6..2092548 100644
--- a/src/bjb-share.c
+++ b/src/bjb-share.c
@@ -20,6 +20,8 @@
 static gchar *
 mail_str ( gchar * string )
 {
+  if (!string)
+    return g_strdup ("''");
   return biji_str_replace (string, "\n", " ");
 }