JS: fixed <Type>Array.iterator methods; added -Xtypedarray compiler key

The <Type>Array.iterator used to lack next<Type>() method (KT-16626).

The -Xtypedarray compiler key enables translation of primitive arrays
to TypedArrays, and primitive array`is`-checks (KT-15358, KT-14007,
KT-14614, KT-16056).

generators/src/org/jetbrains/kotlin/generators/tests/GenerateTests.kt

@@ -1277,6 +1277,10 @@ fun main(args: Array<String>) {
         testClass<AbstractEnumValuesInlineTests> {
             model("codegen/boxInline/enum/", targetBackend = TargetBackend.JS)
         }
+
+        testClass<AbstractJsTypedArraysBoxTest> {
+            model("codegen/box/arrays", targetBackend = TargetBackend.JS)
+        }
     }
 }