Fix Reflect.construct wrt proxy, generator, and non-subclass new.target

src/runtime/runtime-function.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/runtime/runtime-utils.h"
 
 #include "src/accessors.h"
 #include "src/arguments.h"
 #include "src/compiler.h"
 #include "src/deoptimizer.h"
@@ skipping 37 matching lines @@
 
 
 RUNTIME_FUNCTION(Runtime_CompleteFunctionConstruction) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 3);
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, func, 0);
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, constructor, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, unchecked_new_target, 2);
   func->shared()->set_name_should_print_as_anonymous(true);
 
+  if (unchecked_new_target->IsUndefined()) return *func;
+
+  Handle<JSReceiver> new_target =
+      Handle<JSReceiver>::cast(unchecked_new_target);
   // If new.target is equal to |constructor| then the function |func| created
   // is already correctly setup and nothing else should be done here.
   // But if new.target is not equal to |constructor| then we are have a
   // Function builtin subclassing case and therefore the function |func|
   // has wrong initial map. To fix that we create a new function object with
   // correct initial map.
-  if (unchecked_new_target->IsUndefined() ||
-      *constructor == *unchecked_new_target) {
-    return *func;
-  }
+  if (*constructor == *new_target) return *func;
 
   // Create a new JSFunction object with correct initial map.
   HandleScope handle_scope(isolate);
-  Handle<JSFunction> new_target =
-      Handle<JSFunction>::cast(unchecked_new_target);
 
   DCHECK(constructor->has_initial_map());
-  Handle<Map> initial_map =
-      JSFunction::EnsureDerivedHasInitialMap(new_target, constructor);
+  Handle<Map> initial_map;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, initial_map,
+      JSFunction::GetDerivedMap(isolate, constructor, new_target));
 
   Handle<SharedFunctionInfo> shared_info(func->shared(), isolate);
   Handle<Context> context(func->context(), isolate);
   Handle<JSFunction> result =
       isolate->factory()->NewFunctionFromSharedFunctionInfo(
           initial_map, shared_info, context, NOT_TENURED);
   DCHECK_EQ(func->IsConstructor(), result->IsConstructor());
   return *result;
 }
 
@@ skipping 535 matching lines @@
 
 RUNTIME_FUNCTION(Runtime_ThrowStrongModeTooFewArguments) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 0);
   THROW_NEW_ERROR_RETURN_FAILURE(isolate,
                                  NewTypeError(MessageTemplate::kStrongArity));
 }
 
 }  // namespace internal
 }  // namespace v8