NewAKString is effectively the default for any new IDL interface, so
let's mark this as the default behavior. It also makes it much easier to
figure out whatever interfaces are still left to port over to new AK
String.
This is used surprisingly often. For example, it is used by a core
YouTube library called Structured Page Fragments.
It allows you to manually dispatch an event with arbitrary data
attached to it.
The only thing missing from this implementation is the constructor.
This is because WrapperGenerator is currently missing dictionary
capabilities.
