MFA authn flow - matching against multiple contexts?

[Jim Fox]

> It looks like this was way easier than I was making it.  This seems to work
>                 var logger = Java.type("org.slf4j.LoggerFactory").getLogger("net.shibboleth.idp.script.MFAflow");
>                 nextFlow = 'authn/remoteusertoken';
> 
>                 authCtx = input.getSubcontext("net.shibboleth.idp.authn.context.AuthenticationContext");
>                 mfaCtx = authCtx.getSubcontext("net.shibboleth.idp.authn.context.MultiFactorAuthenticationContext");
> 
>                 if (mfaCtx.isAcceptable()) {
>                     nextFlow = null;
>                 }
> 
>                 nextFlow;
>

The reason I was wary of isAcceptable() is that we have SPs that ask for 
Password but really want 2-factor.  The MFA flow deals with that, but I 
think the isAcceptable() wouldn't know anything about it.

Jim