Introduce IsUndefined(Isolate*) and IsTheHole(Isolate*)

src/json-stringifier.cc

 // Copyright 2016 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/json-stringifier.h"
 
 #include "src/conversions.h"
 #include "src/lookup.h"
 #include "src/messages.h"
 #include "src/objects-inl.h"
@@ skipping 73 matching lines @@
 JsonStringifier::JsonStringifier(Isolate* isolate)
     : isolate_(isolate), builder_(isolate), gap_(nullptr), indent_(0) {
   tojson_string_ = factory()->toJSON_string();
   stack_ = factory()->NewJSArray(8);
 }
 
 MaybeHandle<Object> JsonStringifier::Stringify(Handle<Object> object,
                                                Handle<Object> replacer,
                                                Handle<Object> gap) {
   if (!InitializeReplacer(replacer)) return MaybeHandle<Object>();
-  if (!gap->IsUndefined() && !InitializeGap(gap)) return MaybeHandle<Object>();
+  if (!gap->IsUndefined(isolate_) && !InitializeGap(gap)) {
+    return MaybeHandle<Object>();
+  }
   Result result = SerializeObject(object);
   if (result == UNCHANGED) return factory()->undefined_value();
   if (result == SUCCESS) return builder_.Finish();
   DCHECK(result == EXCEPTION);
   return MaybeHandle<Object>();
 }
 
 bool IsInList(Handle<String> key, List<Handle<String> >* list) {
   // TODO(yangguo): This is O(n^2) for n properties in the list. Deal with this
   // if this becomes an issue.
@@ skipping 577 matching lines @@
     if (object->IsOneByteRepresentationUnderneath()) {
       SerializeString_<uint8_t, uc16>(object);
     } else {
       SerializeString_<uc16, uc16>(object);
     }
   }
 }
 
 }  // namespace internal
 }  // namespace v8