[vala/0.40] codegen: Actually create method cast for base interface method as needed

[Rico Tzschichholz <ricotz src gnome org>]

commit de926cb3307e1c08f39bc52b34a1c6be86231c53
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sun Nov 25 18:27:32 2018 +0100

    codegen: Actually create method cast for base interface method as needed
    
    Keep the fallback to base method for now.
    
    This will silence some incompatible pointer type warnings.

 codegen/valagtypemodule.vala | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/codegen/valagtypemodule.vala b/codegen/valagtypemodule.vala
index f9797e18d..06b11b95a 100644
--- a/codegen/valagtypemodule.vala
+++ b/codegen/valagtypemodule.vala
@@ -1448,10 +1448,11 @@ public class Vala.GTypeModule : GErrorModule {
                                        // method inherited from base class
 
                                        var base_method = cl_method;
-                                       if (cl_method.base_method != null) {
-                                               base_method = cl_method.base_method;
-                                       } else if (cl_method.base_interface_method != null) {
+                                       if (cl_method.base_interface_method != null) {
                                                base_method = cl_method.base_interface_method;
+                                       } else if (cl_method.base_method != null) {
+                                               //FIXME should this ever be possible here?
+                                               base_method = cl_method.base_method;
                                        }
 
                                        generate_method_declaration (base_method, cfile);