[evolution] Bug #711824 - Crash due to use-after-free after pine import

[Milan Crha <mcrha src gnome org>]

commit a05f4a91980188bdc5a477a209c79a47dc5f19d8
Author: Milan Crha <mcrha redhat com>
Date:   Wed Nov 20 21:57:13 2013 +0100

    Bug #711824 - Crash due to use-after-free after pine import

 mail/importers/mail-importer.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/mail/importers/mail-importer.c b/mail/importers/mail-importer.c
index ac432b5..a8f8d72 100644
--- a/mail/importers/mail-importer.c
+++ b/mail/importers/mail-importer.c
@@ -272,7 +272,7 @@ mail_importer_import_mbox_sync (EMailSession *session,
        m->path = g_strdup (path);
        m->uri = g_strdup (folderuri);
        if (cancellable)
-               m->base.cancellable = cancellable;
+               m->base.cancellable = g_object_ref (cancellable);
 
        cancellable = m->base.cancellable;