Converter:

Omit Unit return type
Refactor handling of Unit type: extract separate object UnitType

j2k/tests/testData/ast/list/ForEach.ide.kt

@@ -1,6 +1,6 @@
 import java.util.*
 public open class ForEach() {
-public open fun test() : Unit {
+public open fun test() {
 val xs = ArrayList<Any>()
 val ys = LinkedList<Any>()
 for (x in xs)

j2k/tests/testData/ast/list/ForEach.kt

@@ -1,6 +1,6 @@
 import java.util.*
 public open class ForEach() {
-public open fun test() : Unit {
+public open fun test() {
 var xs : ArrayList<Any?>? = ArrayList<Any?>()
 var ys : MutableList<Any?>? = LinkedList<Any?>()
 for (x in xs!!)

j2k/tests/testData/ast/list/Lists.ide.kt

@@ -1,6 +1,6 @@
 import java.util.*
 public open class Lists() {
-public open fun test() : Unit {
+public open fun test() {
 val xs = ArrayList<Any>()
 val ys = LinkedList<Any>()
 val zs = ArrayList<Any>()

j2k/tests/testData/ast/list/Lists.kt

@@ -1,6 +1,6 @@
 import java.util.*
 public open class Lists() {
-public open fun test() : Unit {
+public open fun test() {
 var xs : MutableList<Any?>? = ArrayList<Any?>()
 var ys : MutableList<Any?>? = LinkedList<Any?>()
 var zs : ArrayList<Any?>? = ArrayList<Any?>()