=== tests/cases/compiler/functionOverloads6.ts ===
class foo { 
>foo : foo

   static fnOverload();
>fnOverload : { (): any; (foo: string): any; }

   static fnOverload(foo:string);
>fnOverload : { (): any; (foo: string): any; }
>foo : string

   static fnOverload(foo?: any){ }
>fnOverload : { (): any; (foo: string): any; }
>foo : any
}