[gnome-control-center] user-accounts: Fix button sensitivity in photo dialogue

[Bastien Nocera <hadess src gnome org>]

commit 5c5d608730ca5cd1276c5caf178865e7c6ae6bf5
Author: Bastien Nocera <hadess hadess net>
Date:   Sun Feb 12 20:09:44 2017 +0100

    user-accounts: Fix button sensitivity in photo dialogue
    
    g_file_info_get_content_type() returns an internal string, and we were
    freeing the file_info we got it from in the next line, so it's a miracle
    that the mime_type was ever not garbage.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=778424

 panels/user-accounts/um-photo-dialog.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/panels/user-accounts/um-photo-dialog.c b/panels/user-accounts/um-photo-dialog.c
index ae1e630..2ff11a3 100644
--- a/panels/user-accounts/um-photo-dialog.c
+++ b/panels/user-accounts/um-photo-dialog.c
@@ -157,7 +157,7 @@ update_preview (GtkFileChooser               *chooser,
 
         if (uri) {
                 GdkPixbuf *pixbuf = NULL;
-                const gchar *mime_type = NULL;
+                char *mime_type = NULL;
                 GFile *file;
                 GFileInfo *file_info;
                 GtkWidget *preview;
@@ -173,7 +173,7 @@ update_preview (GtkFileChooser               *chooser,
 
                 if (file_info != NULL &&
                     g_file_info_get_file_type (file_info) != G_FILE_TYPE_DIRECTORY) {
-                        mime_type = g_file_info_get_content_type (file_info);
+                        mime_type = g_strdup (g_file_info_get_content_type (file_info));
                         g_object_unref (file_info);
                 }
 
@@ -181,6 +181,7 @@ update_preview (GtkFileChooser               *chooser,
                         pixbuf = gnome_desktop_thumbnail_factory_generate_thumbnail (thumb_factory,
                                                                                      uri,
                                                                                      mime_type);
+                        g_free (mime_type);
                 }
 
                 gtk_dialog_set_response_sensitive (GTK_DIALOG (chooser),