JS: move more test to box tests

js/js.translator/testData/box/multideclaration/multiValInIntFor.kt

@@ -0,0 +1,21 @@
+package foo
+
+operator fun Int.component1(): Int {
+    return this + 10;
+}
+
+operator fun Int.component2(): String = "b"
+
+fun box(): String {
+    var i = 0;
+    var s = "";
+    for ((a, b) in 1..4) {
+        i = a
+        s = b
+    }
+
+    if (i != 14) return "i != 14, it: $i"
+    if (s != "b") return "s != 'b', it: $s"
+
+    return "OK"
+}