fix for KT-237

idea/testData/codegen/regressions/kt237.jet

@@ -0,0 +1,20 @@
+fun foreach(array: Array<Int>, action: fun(Int): Unit) {
+    for (el in array) {
+       action(el) //exception through compilation (see below)
+    }
+}
+/*
+fun almostFilter(array: Array<Int>, action: fun(Int): Int) {
+    for (el in array) {
+       action(el)
+    }
+}
+*/
+fun box() : String {
+    val a = Array<Int> (3)
+    a[0] = 0
+    a[1] = 1
+    a[2] = 2
+    foreach(a, { (el : Int) : Unit => System.out?.println(el) })
+    return "OK"
+}