Do not add named vars to used_local_names

Commit 67f4019 accidentally reverted
java_bytecode_convert_methodt::variable to an earlier version. This
restores the version as of branch smowton/find_scopes_for_anonymous_variables

Fixes failure of test cbmc-java/inferlexicalscope1

Author: smowton

src/java_bytecode/java_bytecode_convert_method.cpp

@@ -171,8 +171,6 @@ const exprt java_bytecode_convert_methodt::variable(
   else
   {
     exprt result=var.symbol_expr;
-    if(!var.is_parameter)
-      used_local_names.insert(to_symbol_expr(result));
     if(do_cast==CAST_AS_NEEDED && t!=result.type())
       result=typecast_exprt(result, t);
     return result;