JS: move expressions test to box tests

js/js.translator/testData/box/expression/cast/castToArray.kt

@@ -0,0 +1,15 @@
+package foo
+
+fun box(): String {
+    val ints: Any? = arrayOf(1, 2)
+    val strings: Any? = arrayOf("a", "b")
+    val nil: Any? = null
+    val obj: Any? = object{}
+
+    success("ints") { ints as Array<*> }
+    success("strings") { strings as Array<*> }
+    failsClassCast("null") { nil as Array<*> }
+    failsClassCast("obj") { obj as Array<*> }
+
+    return "OK"
+}