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).

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/K2JSCompilerArguments.java

@@ -71,6 +71,10 @@ public class K2JSCompilerArguments extends CommonCompilerArguments {
     @ValueDescription("<path>")
     public String outputPostfix;
 
+    @GradleOption(DefaultValues.BooleanFalseDefault.class)
+    @Argument(value = "Xtypedarrays", description = "Translate primitive arrays to JS typed arrays")
+    public boolean typedArrays;
+
     @NotNull
     public static K2JSCompilerArguments createDefaultInstance() {
         K2JSCompilerArguments arguments = new K2JSCompilerArguments();