Use resolver to translate cpp_name to scoped base_name

Author: tautschnig

regression/cpp/enum1/test.desc

@@ -1,4 +1,4 @@
-KNOWNBUG
+CORE
 main.cpp
 -std=c++11
 ^EXIT=0$

src/cpp/cpp_typecheck_enum_type.cpp

@@ -91,6 +91,8 @@ void cpp_typecheckt::typecheck_enum_type(typet &type)
   bool anonymous=!enum_type.has_tag();
   irep_idt base_name;
 
+  cpp_save_scopet save_scope(cpp_scopes);
+
   if(anonymous)
   {
     // we fabricate a tag based on the enum constants contained
@@ -100,14 +102,11 @@ void cpp_typecheckt::typecheck_enum_type(typet &type)
   {
     const cpp_namet &tag=enum_type.tag();
 
-    if(tag.is_simple_name())
-      base_name=tag.get_base_name();
-    else
-    {
-      error().source_location=type.source_location();
-      error() << "enum tag is expected to be a simple name" << eom;
-      throw 0;
-    }
+    cpp_template_args_non_tct template_args;
+    template_args.make_nil();
+
+    cpp_typecheck_resolvet resolver(*this);
+    resolver.resolve_scope(tag, base_name, template_args);
   }
 
   bool has_body=enum_type.has_body();