[stubs] Introduce NonPrimitiveToPrimitive builtin.

src/objects.cc

 // Copyright 2015 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/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <sstream>
 
@@ skipping 8030 matching lines @@
 
 // static
 MaybeHandle<Object> JSReceiver::ToPrimitive(Handle<JSReceiver> receiver,
                                             ToPrimitiveHint hint) {
   Isolate* const isolate = receiver->GetIsolate();
   Handle<Object> exotic_to_prim;
   ASSIGN_RETURN_ON_EXCEPTION(
       isolate, exotic_to_prim,
       GetMethod(receiver, isolate->factory()->to_primitive_symbol()), Object);
   if (!exotic_to_prim->IsUndefined(isolate)) {
-    Handle<Object> hint_string;
-    switch (hint) {
-      case ToPrimitiveHint::kDefault:
-        hint_string = isolate->factory()->default_string();
-        break;
-      case ToPrimitiveHint::kNumber:
-        hint_string = isolate->factory()->number_string();
-        break;
-      case ToPrimitiveHint::kString:
-        hint_string = isolate->factory()->string_string();
-        break;
-    }
+    Handle<Object> hint_string =
+        isolate->factory()->ToPrimitiveHintString(hint);
     Handle<Object> result;
     ASSIGN_RETURN_ON_EXCEPTION(
         isolate, result,
         Execution::Call(isolate, exotic_to_prim, receiver, 1, &hint_string),
         Object);
     if (result->IsPrimitive()) return result;
     THROW_NEW_ERROR(isolate,
                     NewTypeError(MessageTemplate::kCannotConvertToPrimitive),
                     Object);
   }
@@ skipping 10861 matching lines @@
 
   Object* data_obj =
       constructor->shared()->get_api_func_data()->access_check_info();
   if (data_obj->IsUndefined(isolate)) return nullptr;
 
   return AccessCheckInfo::cast(data_obj);
 }
 
 }  // namespace internal
 }  // namespace v8