Static readonly fields generate actual initializer values

Static readonly fields in TS generate actual initializer values in Kotlin, which is invalid.

Source TS:

export declare class Spinner {
  static readonly SIZE_SMALL = 20;
  static readonly SIZE_STANDARD = 50;
  static readonly SIZE_LARGE = 100;
}

Generated:

external open class Spinner {
    companion object {
        var SIZE_SMALL = 20
        var SIZE_STANDARD = 50
        var SIZE_LARGE = 100
    }
}

Which gives the following compile error:

Wrong initializer of external declaration. Must be ' = definedExternally'

This was noticed in version 0.5.8-rc.0 of Dukat.

Kotlin / dukat