PSA: You no longer need to write (struct {}) in FIDL

[Mitchell Kember]

You can stop reading if you don't write FIDL code.

The FIDL syntax for empty responses has been simplified.

Before, empty responses had to be written (struct {}) if the method had an error:

protocol Foo {

    Bar() -> (struct {}) error uint32;

}

Now, you can simply write empty parentheses:

protocol Foo {

    Bar() -> () error uint32;

}

Both are allowed right now, but soon only the new way will be allowed. I will migrate all existing code.

See fxbug.dev/112767 for details.