Cpp: Make a specialized scope correctly set the parent type

Cython/Compiler/Symtab.py

@@ -2624,6 +2624,7 @@ class CppClassScope(Scope):
     def specialize(self, values, type_entry):
         scope = CppClassScope(self.name, self.outer_scope)
         scope.type = type_entry
+        type_entry.set_scope(scope)
         for entry in self.entries.values():
             if entry.is_type:
                 scope.declare_type(entry.name,