[libgda] Corrected usage of assert function

[Vivien Malerba <vivien src gnome org>]

commit 2fc2f683153e7e5fd45e585db85f5f8cdaee5144
Author: Vivien Malerba <malerba gnome-db org>
Date:   Tue Nov 18 20:22:42 2014 +0100

    Corrected usage of assert function

 tools/common/t-context.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/tools/common/t-context.c b/tools/common/t-context.c
index 422ad19..db4cdd8 100644
--- a/tools/common/t-context.c
+++ b/tools/common/t-context.c
@@ -454,7 +454,7 @@ t_context_get_id (TContext *console)
 void
 t_context_set_command_group (TContext *console, ToolCommandGroup *group)
 {
-       g_return_val_if_fail (T_IS_CONTEXT (console), NULL);
+       g_return_if_fail (T_IS_CONTEXT (console));
        console->priv->command_group = group;
 }