Add an API to create a detached global object

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 86135fd83d2ab6460a8e96665a651f8a1af42f05..d9f85d6c5cca63246925aebb0b1f6fbde2649876 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -5619,11 +5619,40 @@ const char* v8::V8::GetVersion() {
   return i::Version::GetVersion();
 }
 
-static i::Handle<i::Context> CreateEnvironment(
+template <typename ObjectType>
+struct InvokeBootstrapper;
+
+template <>
+struct InvokeBootstrapper<i::Context> {
+  i::Handle<i::Context> Invoke(
+      i::Isolate* isolate, i::MaybeHandle<i::JSGlobalProxy> maybe_global_proxy,
+      v8::Local<v8::ObjectTemplate> global_object_template,
+      v8::ExtensionConfiguration* extensions, size_t context_snapshot_index) {
+    return isolate->bootstrapper()->CreateEnvironment(
+        maybe_global_proxy, global_object_template, extensions,
+        context_snapshot_index);
+  }
+};
+
+template <>
+struct InvokeBootstrapper<i::JSGlobalProxy> {
+  i::Handle<i::JSGlobalProxy> Invoke(
+      i::Isolate* isolate, i::MaybeHandle<i::JSGlobalProxy> maybe_global_proxy,
+      v8::Local<v8::ObjectTemplate> global_object_template,
+      v8::ExtensionConfiguration* extensions, size_t context_snapshot_index) {
+    USE(maybe_global_proxy);
+    USE(extensions);
+    USE(context_snapshot_index);
+    return isolate->bootstrapper()->NewDetachedGlobal(global_object_template);
+  }
+};
+
+template <typename ObjectType>
+static i::Handle<ObjectType> CreateEnvironment(
     i::Isolate* isolate, v8::ExtensionConfiguration* extensions,
     v8::Local<ObjectTemplate> global_template,
     v8::Local<Value> maybe_global_proxy, size_t context_snapshot_index) {
-  i::Handle<i::Context> env;
+  i::Handle<ObjectType> result;
 
   // Enter V8 via an ENTER_V8 scope.
   {
@@ -5666,8 +5695,9 @@ static i::Handle<i::Context> CreateEnvironment(
       maybe_proxy = i::Handle<i::JSGlobalProxy>::cast(proxy);
     }
     // Create the environment.
-    env = isolate->bootstrapper()->CreateEnvironment(
-        maybe_proxy, proxy_template, extensions, context_snapshot_index);
+    InvokeBootstrapper<ObjectType> invoke;
+    result = invoke.Invoke(isolate, maybe_proxy, proxy_template, extensions,
+                           context_snapshot_index);
 
     // Restore the access check info on the global template.
     if (!global_template.IsEmpty()) {
@@ -5681,7 +5711,7 @@ static i::Handle<i::Context> CreateEnvironment(
   }
   // Leave V8.
 
-  return env;
+  return result;
 }
 
 Local<Context> NewContext(v8::Isolate* external_isolate,
@@ -5695,8 +5725,8 @@ Local<Context> NewContext(v8::Isolate* external_isolate,
   ExtensionConfiguration no_extensions;
   if (extensions == NULL) extensions = &no_extensions;
   i::Handle<i::Context> env =
-      CreateEnvironment(isolate, extensions, global_template, global_object,
-                        context_snapshot_index);
+      CreateEnvironment<i::Context>(isolate, extensions, global_template,
+                                    global_object, context_snapshot_index);
   if (env.is_null()) {
     if (isolate->has_pending_exception()) {
       isolate->OptionalRescheduleException(true);
@@ -5727,6 +5757,35 @@ MaybeLocal<Context> v8::Context::FromSnapshot(
                     global_object, context_snapshot_index);
 }
 
+Local<Object> v8::Context::NewDetachedGlobal(
+    v8::Isolate* external_isolate, v8::Local<ObjectTemplate> global_template) {
+  i::Isolate* isolate = reinterpret_cast<i::Isolate*>(external_isolate);
+  LOG_API(isolate, Context, NewDetachedGlobal);
+  i::HandleScope scope(isolate);
+  i::Handle<i::FunctionTemplateInfo> global_constructor =
+      EnsureConstructor(isolate, *global_template);
+  Utils::ApiCheck(global_constructor->needs_access_check(),
+                  "v8::Context::NewDetachedGlobal",
+                  "Global template needs to have access checks enabled.");
+  i::Handle<i::AccessCheckInfo> access_check_info = i::handle(
+      i::AccessCheckInfo::cast(global_constructor->access_check_info()),
+      isolate);
+  Utils::ApiCheck(access_check_info->named_interceptor() != nullptr,
+                  "v8::Context::NewDetachedGlobal",
+                  "Global template needs to have access check handlers.");
+  i::Handle<i::JSGlobalProxy> global_proxy =
+      CreateEnvironment<i::JSGlobalProxy>(isolate, nullptr, global_template,
+                                          v8::Local<v8::Value>(), 0);
+  if (global_proxy.is_null()) {
+    if (isolate->has_pending_exception()) {
+      isolate->OptionalRescheduleException(true);
+    }
+    return Local<Object>();
+  }
+  return Utils::ToLocal(
+      scope.CloseAndEscape(i::Handle<i::JSObject>::cast(global_proxy)));
+}
+
 void v8::Context::SetSecurityToken(Local<Value> token) {
   i::Handle<i::Context> env = Utils::OpenHandle(this);
   i::Handle<i::Object> token_handle = Utils::OpenHandle(*token);