[css-layout-api] VoidFunction is also defined in another spec

[bzbarsky]

https://drafts.css-houdini.org/css-layout-api/#registering-a-layout has:

callback VoidFunction = void ();

but VoidFunction is also defined in https://webaudio.github.io/web-audio-api/#AudioWorkletGlobalScope and a conformant IDL parser will error out on the duplicate definition of the name.

We could change IDL to allow this sort of thing: identical callback definition sharing a name. Or we could change these two specs to reference VoidFunction as defined in some one place.

[tabatkins]

Like, say, the Infra spec over in WHATWG?

[bzbarsky]

That would be a reasonable place for something like this, yes.

[annevk]

From @foolip:

https://heycam.github.io/webidl/#common already has VoidFunction.

[annevk]

Filed WebAudio/web-audio-api#1132 on Web Audio.

[bfgeek]

I've removed this from both the paint and layout specs.