JS: make tests dependent on primitive array is checks pass even when -Xtypedarray is disabled (related: KT-17137)

compiler/testData/codegen/box/arrays/kt2997.kt

@@ -1,6 +1,4 @@
 //KT-2997 Automatically cast error (Array)
-// IGNORE_BACKEND_WITHOUT_CHECK: JS
-// Unmute when JS implements primitive arrays via TypedArray
 
 fun foo(a: Any): Int {
     if (a is IntArray) {
@@ -55,6 +53,9 @@ fun foo(a: Any): Int {
 }
 
 fun box(): String {
+    // Only run this test if primitive array `is` checks work (KT-17137)
+    if ((intArrayOf() as Any) is Array<*>) return "OK"
+
     val iA = IntArray(1)
     if (foo(iA) != 1) return "fail int[]"
     val sA = ShortArray(1)