JS: move more test to box tests

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

@@ -0,0 +1,41 @@
+package foo
+
+class A {
+    operator fun component1(): Int = 1
+}
+operator fun A.component2(): String = "n"
+
+class B {
+    operator fun component1(): Int = 1
+    operator fun component2(): Int = 2
+    operator fun component3(): Int = 3
+}
+
+class C {
+    operator fun component1(): Int = 42
+}
+
+fun box(): String {
+    val (a, b) = A()
+    if (a != 1) return "a != 1, it: $a"
+    if (b != "n") return "b != 'n', it: $b"
+
+    var (x, y) = A()
+    if (x != 1) return "x != 1, it: $x"
+    if (y != "n") return "y != 'n', it: $y"
+
+    x = 3
+    if (x != 3) return "x != 3, it: $x"
+    y = "m"
+    if (y != "m") return "y != 'm', it: $y"
+
+    var (b1, b2, b3) = B()
+    if (b1 != 1) return "b1 != 1, it: $b1"
+    if (b2 != 2) return "b2 != 2, it: $b2"
+    if (b3 != 3) return "b3 != 3, it: $b3"
+
+    val (c) = C()
+    if (c != 42) return "c != 42, it: $c"
+
+    return "OK"
+}