Taking ownership of the receiver

Summary

• Support traits that use fn(self) with dynamic dispatch
  • The caller will have to be using a Box<dyn Foo>, but that is not hard-coded into the trait.

Status quo

Grace is working on an embedded system. She needs to parse data from an input stream that is formatted as a series of packets in the format TLA. She finds a library tla on crates.io with a type that implements the async iterator trait: