[K/JS] test(@JsExport): add few more tests on export after ExportModel discussion meeting.

js/js.translator/testData/box/export/vararg.kt

@@ -0,0 +1,30 @@
+// IGNORE_BACKEND: JS
+// EXPECTED_REACHABLE_NODES: 1270
+// SKIP_MINIFICATION
+// RUN_PLAIN_BOX_FUNCTION
+// INFER_MAIN_MODULE
+
+// MODULE: vararg
+// FILE: lib.kt
+@JsExport
+fun uintVararg(vararg uints: UInt): String {
+    for (u in uints)  {
+        if (u == 0u) return "Failed"
+    }
+
+    return "OK"
+}
+
+@JsExport
+fun uint(a: Int): UInt {
+    return a.toUInt()
+}
+
+// FILE: test.js
+function box() {
+    var vararg = this.vararg
+    var uintVararg = vararg.uintVararg
+    var uint = vararg.uint
+
+    return uintVararg([uint(1), uint(2), uint(3)])
+}