[vala] codegen: Actually write declaration for GNodeTraverseFunc wrapper

[Rico Tzschichholz <ricotz src gnome org>]

commit 4056b1c18cd93cac40f1a442fd0238d48cf11cff
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sat Aug 26 21:50:08 2017 +0200

    codegen: Actually write declaration for GNodeTraverseFunc wrapper
    
    This fixes a very old typo which causes the wrong declaration to be written
    and results in a double definition.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786845

 codegen/valaccodebasemodule.vala |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index a3f1b26..1d0610c 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -3234,7 +3234,7 @@ public abstract class Vala.CCodeBaseModule : CodeGenerator {
                        ccode.add_return (new CCodeConstant ("FALSE"));
 
                        pop_function ();
-                       cfile.add_function_declaration (function);
+                       cfile.add_function_declaration (wrapper);
                        cfile.add_function (wrapper);
 
                        /* Now the code to call g_traverse with the above */