when jruby is not coming from the thread.currentThread.contextClassLoade...

...r then ScriptingContainer

does not work out of the box, dito with JRubyEngineFactory using a wrong value or 'none' value for the classloader
system property (org.jruby.embed.classloader)

@enebo as either this or the pull request: https://github.com/jruby/jruby/pull/2023
both have add some testcases. this one adds some cases where ScriptingContainer or JRubyScriptEngine fail to run ruby scripts. and with #2023 the tests show the opposite result. the intention is at least to test those "features" as expected behaviour.