[Tests] Migrate backend-independent tests from native to compiler/testData.

^KT-65979

compiler/testData/codegen/box/branching/when5.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the LICENSE file.
+ */
+// WITH_STDLIB
+
+import kotlin.test.*
+
+fun when5(i: Int): Int {
+  when (i) {
+    0 -> return 42
+    1 -> return 4
+    2 -> return 3
+    3 -> return 2
+    4 -> return 1
+    else -> return 24
+  }
+}
+
+fun box(): String {
+  val res = when5(2)
+  if (res != 3) return "FAIL $res"
+
+  return "OK"
+}