Add test for array modification within for-in-array-withIndex loop body

compiler/testData/codegen/box/controlStructures/forInArrayWithIndex/forInArrayWithIndexContinuesAsUnmodified.kt

@@ -0,0 +1,30 @@
+// See https://youtrack.jetbrains.com/issue/KT-22424
+// IGNORE_BACKEND: JS
+// WITH_RUNTIME
+
+fun testUnoptimized(): String {
+    var arr = intArrayOf(1, 2, 3, 4)
+    val sb = StringBuilder()
+    val ixs = arr.withIndex()
+    for ((i, x) in ixs) {
+        sb.append("$i:$x;")
+        arr = intArrayOf(10, 20)
+    }
+    return sb.toString()
+}
+
+fun box(): String {
+    val tn = testUnoptimized()
+
+    var arr = intArrayOf(1, 2, 3, 4)
+    val sb = StringBuilder()
+    for ((i, x) in arr.withIndex()) {
+        sb.append("$i:$x;")
+        arr = intArrayOf(10, 20)
+    }
+
+    val s = sb.toString()
+    if (s != "0:1;1:2;2:3;3:4;") return "Fail: '$s'; unoptimized: '$tn'"
+
+    return "OK"
+}