[JS IR] Review remarks

- Move origin to common place
- Add comments and todo about solution
- Remove MODULE directive from tests
- Add test with in-place using of js function

js/js.translator/testData/box/reflection/kClassWithJsCall.kt

@@ -1,6 +1,5 @@
 import kotlin.reflect.KClass
 
-// MODULE: main
 // FILE: main.kt
 external abstract open class A(
     o: String