=== tests/cases/compiler/fatarrowfunctionsInFunctionParameterDefaults.ts ===
function fn(x = () => this, y = x()) {
>fn : (x?: () => any, y?: any) => any
>x : () => any
>() => this : () => any
>this : any
>y : any
>x() : any
>x : () => any

    // should be 4
    return y;
>y : any

}

fn.call(4); // Should be 4
>fn.call(4) : any
>fn.call : (thisArg: any, ...argArray: any[]) => any
>fn : (x?: () => any, y?: any) => any
>call : (thisArg: any, ...argArray: any[]) => any