[gnome-online-accounts] mail-auth, mail-client: Be more strict about what is acceptable

[Debarshi Ray <debarshir src gnome org>]

commit 783767039e74e7600b0fdd7eada45661b83e2acb
Author: Debarshi Ray <debarshir gnome org>
Date:   Wed Jan 4 16:38:16 2017 +0100

    mail-auth, mail-client: Be more strict about what is acceptable

 src/goabackend/goamailauth.c   |    2 ++
 src/goabackend/goamailclient.c |    1 +
 2 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/goabackend/goamailauth.c b/src/goabackend/goamailauth.c
index 9939791..bcd6ef5 100644
--- a/src/goabackend/goamailauth.c
+++ b/src/goabackend/goamailauth.c
@@ -222,6 +222,7 @@ goa_mail_auth_run_finish (GoaMailAuth         *self,
 {
   GTask *task;
 
+  g_return_val_if_fail (GOA_IS_MAIL_AUTH (self), FALSE);
   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 
   g_return_val_if_fail (g_task_is_valid (res, self), FALSE);
@@ -272,6 +273,7 @@ goa_mail_auth_starttls_finish (GoaMailAuth         *self,
 {
   GTask *task;
 
+  g_return_val_if_fail (GOA_IS_MAIL_AUTH (self), FALSE);
   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 
   g_return_val_if_fail (g_task_is_valid (res, self), FALSE);
diff --git a/src/goabackend/goamailclient.c b/src/goabackend/goamailclient.c
index 25176bb..6793fbf 100644
--- a/src/goabackend/goamailclient.c
+++ b/src/goabackend/goamailclient.c
@@ -410,6 +410,7 @@ goa_mail_client_check_finish (GoaMailClient *self, GAsyncResult *res, GError **e
 {
   GTask *task;
 
+  g_return_val_if_fail (GOA_IS_MAIL_CLIENT (self), FALSE);
   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 
   g_return_val_if_fail (g_task_is_valid (res, self), FALSE);