Creates a new protocol instance.
- iOS 4.3+
- macOS 10.7+
- tvOS 9.0+
- watchOS 1.0+
The name of the protocol you want to create.
A new protocol instance or
nil if a protocol with the same name as
name already exists.
You must register the returned protocol instance with the
objc_register function before you can use it.
There is no dispose method associated with this function.