MagLev/maglev — pull request #225 by timfel (2013-01-28 14:03:14+00:00)
Title: Kernel#extended should not be defined.

```
% grep -A1 -B2 def.extended src/kernel/bootstrap/Module.rb
# Callback invoked whenever the receiver is used to extend an object.
# The object is passed as a paramter.
def extended(a_module)
end
```

extended should be called only if `obj.responds_to? :extended`