Add an API to create a detached global object

src/api-natives.cc

Index: src/api-natives.cc
diff --git a/src/api-natives.cc b/src/api-natives.cc
index f09f42d5f0480f76b8d6ac4c0e54efb0f6a9314e..af70bfb161b73d75a68377064715deb2a493179d 100644
--- a/src/api-natives.cc
+++ b/src/api-natives.cc
@@ -539,9 +539,22 @@ Handle<JSFunction> ApiNatives::CreateApiFunction(
     Handle<Object> prototype, ApiInstanceType instance_type) {
   Handle<SharedFunctionInfo> shared =
       FunctionTemplateInfo::GetOrCreateSharedFunctionInfo(isolate, obj);
+  int map_index =
+      Context::FunctionMapIndex(shared->language_mode(), shared->kind());
+  Handle<Map> initial_map(Map::cast(isolate->native_context()->get(map_index)));
+  return CreateApiFunctionWithMap(isolate, isolate->native_context(), obj,
+                                  initial_map, prototype, instance_type);
+}
+
+Handle<JSFunction> ApiNatives::CreateApiFunctionWithMap(
+    Isolate* isolate, Handle<Object> context_or_undefined,
+    Handle<FunctionTemplateInfo> obj, Handle<Map> initial_map,
+    Handle<Object> prototype, ApiInstanceType instance_type) {
+  Handle<SharedFunctionInfo> shared =
+      FunctionTemplateInfo::GetOrCreateSharedFunctionInfo(isolate, obj);
   Handle<JSFunction> result =
       isolate->factory()->NewFunctionFromSharedFunctionInfo(
-          shared, isolate->native_context());
+          initial_map, shared, context_or_undefined);
 
   if (obj->remove_prototype()) {
     result->set_map(*isolate->sloppy_function_without_prototype_map());
@@ -560,12 +573,16 @@ Handle<JSFunction> ApiNatives::CreateApiFunction(
     result->set_map(*isolate->sloppy_function_with_readonly_prototype_map());
   }
 
-  if (prototype->IsTheHole(isolate)) {
-    prototype = isolate->factory()->NewFunctionPrototype(result);
+  if (context_or_undefined->IsContext()) {
+    if (prototype->IsTheHole(isolate)) {
+      prototype = isolate->factory()->NewFunctionPrototype(result);
+    } else {
+      JSObject::AddProperty(Handle<JSObject>::cast(prototype),
+                            isolate->factory()->constructor_string(), result,
+                            DONT_ENUM);
+    }
   } else {
-    JSObject::AddProperty(Handle<JSObject>::cast(prototype),
-                          isolate->factory()->constructor_string(), result,
-                          DONT_ENUM);
+    prototype = isolate->factory()->null_value();

[jochen (gone - plz use gerrit), 2016/06/28 14:27:00]

we can't create a prototype object without the object function which in turn we
can't create without a context. just use null.

   }
 
   int internal_field_count = 0;
@@ -607,7 +624,7 @@ Handle<JSFunction> ApiNatives::CreateApiFunction(
 
   Handle<Map> map =
       isolate->factory()->NewMap(type, instance_size, FAST_HOLEY_SMI_ELEMENTS);
-  JSFunction::SetInitialMap(result, map, Handle<JSObject>::cast(prototype));
+  JSFunction::SetInitialMap(result, map, prototype);
 
   // Mark as undetectable if needed.
   if (obj->undetectable()) {