[es6] Implement spec compliant ToPrimitive in the runtime.

src/objects-inl.h

 // Copyright 2012 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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 1114 matching lines @@
     return IsSmi();
   } else if (FLAG_track_double_fields && representation.IsDouble()) {
     return IsMutableHeapNumber() || IsNumber();
   } else if (FLAG_track_heap_object_fields && representation.IsHeapObject()) {
     return IsHeapObject();
   }
   return true;
 }
 
 
+// static
 MaybeHandle<JSReceiver> Object::ToObject(Isolate* isolate,
                                          Handle<Object> object) {
   return ToObject(
       isolate, object, handle(isolate->context()->native_context(), isolate));
 }
 
 
+// static
+MaybeHandle<Name> Object::ToName(Isolate* isolate, Handle<Object> input) {
+  if (input->IsName()) return Handle<Name>::cast(input);
+  return ToString(isolate, input);
+}
+
+
+// static
+MaybeHandle<Object> Object::ToPrimitive(Handle<Object> input,
+                                        ToPrimitiveHint hint) {
+  if (input->IsPrimitive()) return input;
+  return JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(input), hint);
+}
+
+
 bool Object::HasSpecificClassOf(String* name) {
   return this->IsJSObject() && (JSObject::cast(this)->class_name() == name);
 }
 
 
 MaybeHandle<Object> Object::GetProperty(Handle<Object> object,
                                         Handle<Name> name,
                                         LanguageMode language_mode) {
   LookupIterator it(object, name);
   return GetProperty(&it, language_mode);
@@ skipping 6718 matching lines @@
 #undef READ_INT64_FIELD
 #undef WRITE_INT64_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_