Wrong argument type for trace function - name of scope instead of binding

A trace function has the signature
trace_func(event, file, line, id, binding, klass)

The binding parameter should be an object that allows to lookup variables in the current scope.
The code in Ruby.callTraceFunction that sets this parameter is:
self != null ? self : getNil(),
which basically gives the name/type of the self object.

I believe that something like
context.getCurrentScope().getBindingScope()
would be better.

Mind you: I'm not entirely sure, though, what exactly the Binding class is supposed to be. The documentation is a bit scarce on this.