Expose Array.prototype.values behind a flag and stage it

src/bootstrapper.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/bootstrapper.h"
 
 #include "src/accessors.h"
 #include "src/api-natives.h"
 #include "src/code-stubs.h"
 #include "src/extensions/externalize-string-extension.h"
@@ skipping 2509 matching lines @@
 
   proxy_function->shared()->set_construct_stub(
       *isolate->builtins()->ProxyConstructor_ConstructStub());
   proxy_function->shared()->set_internal_formal_parameter_count(2);
   proxy_function->shared()->set_length(2);
 
   native_context()->set_proxy_function(*proxy_function);
   InstallFunction(global, name, proxy_function, factory->Object_string());
 }
 
+void Genesis::InitializeGlobal_harmony_array_prototype_values() {
+  if (!FLAG_harmony_array_prototype_values) return;
+  Handle<JSFunction> array_constructor(native_context()->array_function());
+  Handle<JSObject> array_prototype(
+      JSObject::cast(array_constructor->instance_prototype()));
+  Handle<Object> values_iterator =
+      JSObject::GetProperty(array_prototype, factory()->iterator_symbol())
+          .ToHandleChecked();
+  DCHECK(values_iterator->IsJSFunction());
+  JSObject::AddProperty(array_prototype, factory()->values_string(),
+                        values_iterator, DONT_ENUM);
+
+  Handle<Object> unscopables =
+      JSObject::GetProperty(array_prototype, factory()->unscopables_symbol())
+          .ToHandleChecked();
+  DCHECK(unscopables->IsJSObject());
+  JSObject::AddProperty(Handle<JSObject>::cast(unscopables),
+                        factory()->values_string(), factory()->true_value(),
+                        NONE);
+}
 
 Handle<JSFunction> Genesis::InstallArrayBuffer(Handle<JSObject> target,
                                                const char* name) {
   // Setup the {prototype} with the given {name} for @@toStringTag.
   Handle<JSObject> prototype =
       factory()->NewJSObject(isolate()->object_function(), TENURED);
   JSObject::AddProperty(prototype, factory()->to_string_tag_symbol(),
                         factory()->NewStringFromAsciiChecked(name),
                         static_cast<PropertyAttributes>(DONT_ENUM | READ_ONLY));
 
@@ skipping 420 matching lines @@
   static const char* harmony_instanceof_natives[] = {nullptr};
   static const char* harmony_restrictive_declarations_natives[] = {nullptr};
   static const char* harmony_regexp_property_natives[] = {nullptr};
   static const char* harmony_function_name_natives[] = {nullptr};
   static const char* harmony_function_sent_natives[] = {nullptr};
   static const char* promise_extra_natives[] = {"native promise-extra.js",
                                                 nullptr};
   static const char* harmony_object_values_entries_natives[] = {nullptr};
   static const char* harmony_object_own_property_descriptors_natives[] = {
       nullptr};
+  static const char* harmony_array_prototype_values_natives[] = {nullptr};
 
   for (int i = ExperimentalNatives::GetDebuggerCount();
        i < ExperimentalNatives::GetBuiltinsCount(); i++) {
 #define INSTALL_EXPERIMENTAL_NATIVES(id, desc)                                \
   if (FLAG_##id) {                                                            \
     for (size_t j = 0; id##_natives[j] != NULL; j++) {                        \
       Vector<const char> script_name = ExperimentalNatives::GetScriptName(i); \
       if (strncmp(script_name.start(), id##_natives[j],                       \
                   script_name.length()) == 0) {                               \
         if (!Bootstrapper::CompileExperimentalBuiltin(isolate(), i)) {        \
@@ skipping 653 matching lines @@
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   DCHECK(!IsActive());
 }
 
 }  // namespace internal
 }  // namespace v8