PropertyWrapper: @invalidating backport

Invalidating.swift

struct Invalidation {
    static let display = Invalidation { $0.setNeedsDisplay() }
    static let layout = Invalidation { $0.setNeedsLayout() }

    let action: (UIView) -> Void
}

@propertyWrapper
struct Invalidating<Value> {
    private let invalidations: [Invalidation]

    var wrappedValue: Value

    init(wrappedValue: Value, _ invalidations: Invalidation...) {
        self.wrappedValue = wrappedValue
        self.invalidations = invalidations
    }

    static subscript<Instance: UIView>(
        _enclosingInstance instance: Instance,
        wrapped wrappedKeyPath: ReferenceWritableKeyPath<Instance, Value>,
        storage storageKeyPath: ReferenceWritableKeyPath<Instance, Self>
    ) -> Value {
        get { instance[keyPath: storageKeyPath].wrappedValue }
        set {
            instance[keyPath: storageKeyPath].wrappedValue = newValue
            instance[keyPath: storageKeyPath].invalidations.forEach { $0.action(instance) }
        }
    }
}