[evolution] e_client_selector_get_client_sync(): Add argument guards.

[Matthew Barnes <mbarnes src gnome org>]

commit a7196dd228263730b9cc4143d2f1ca590e728b7f
Author: Matthew Barnes <mbarnes redhat com>
Date:   Fri Mar 1 13:05:56 2013 -0500

    e_client_selector_get_client_sync(): Add argument guards.

 e-util/e-client-selector.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/e-util/e-client-selector.c b/e-util/e-client-selector.c
index 802310f..e164c80 100644
--- a/e-util/e-client-selector.c
+++ b/e-util/e-client-selector.c
@@ -398,6 +398,9 @@ e_client_selector_get_client_sync (EClientSelector *selector,
        GAsyncResult *result;
        EClient *client;
 
+       g_return_val_if_fail (E_IS_CLIENT_SELECTOR (selector), NULL);
+       g_return_val_if_fail (E_IS_SOURCE (source), NULL);
+
        closure = e_async_closure_new ();
 
        e_client_selector_get_client (