How to get at Form Data from HttpRequestData

This is very similar to #1920.

I am wondering how I can get at the logical form collection for multipart/x-www-url-encoded submissions when working with functions under the isolated worker process model.

Should we be using the same `executionContext.BindingContext.BindingData` approach for handling this scenario?

I would really like some way to obtain a simple `Dictionary` of form data that I can pass into my business logic. We have this working perfectly with in-process model.

Right now, I am staring down a hand-coded body parser task.