gobject-2.0: Fix the Closure.invoke() signature

The return value must be initialized by the caller, as is clear from
GLib's internal callers, and e.g. dummy_closure_marshal() on the callee
side. So it appears the GLib type annotation is incorrect, as it
specifies `out` but should be `inout`.

diff --git a/vapi/gobject-2.0.vapi b/vapi/gobject-2.0.vapi
index c7e3716c1284abdb0a0aed76716f81fdcb6a98ec..d3434b46b3edd2aac1d933e18fc83aac78be05e5 100644 (file)
--- a/vapi/gobject-2.0.vapi
+++ b/vapi/gobject-2.0.vapi
@@ -81,7 +81,7 @@ namespace GLib {
                public void add_invalidate_notifier (void* notify_data, GLib.ClosureNotify notify_func);
                public void add_marshal_guards (void* pre_marshal_data, GLib.ClosureNotify pre_marshal_notify, void* post_marshal_data, GLib.ClosureNotify post_marshal_notify);
                public void invalidate ();
-               public void invoke (out GLib.Value return_value, [CCode (array_length_cname = "n_param_values", array_length_pos = 1.5, array_length_type = "guint")] GLib.Value[] param_values, void* invocation_hint);
+               public void invoke (ref GLib.Value return_value, [CCode (array_length_cname = "n_param_values", array_length_pos = 1.5, array_length_type = "guint")] GLib.Value[] param_values, void* invocation_hint = null);
                [CCode (has_construct_function = false)]
                public Closure.object (uint sizeof_closure, GLib.Object object);
                public unowned GLib.Closure @ref ();