agent-manager: cancel secrets requests on an error

It might be that the user didn't supply the secrets in time and the dbus call
timed out. The agent should now hide the secrets dialog and we must let it know.

https://bugzilla.redhat.com/show_bug.cgi?id=1272023

src/settings/nm-agent-manager.c

@@ -841,6 +841,9 @@ _con_get_request_done (NMSecretAgent *agent,
 			req_complete_error (req, error);
 			g_error_free (error);
 		} else {
+			/* Tell the failed agent we're no longer interested. */
+			nm_secret_agent_cancel_secrets (parent->current, parent->current_call_id);
+
 			/* Try the next agent */
 			request_next_agent (req);
 			maybe_remove_agent_on_error (agent, error);