Make delete API consistent for String objects

test/cctest/test-api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1572 matching lines @@
   ExpectObject("\"test\"", the_string);
   v8::Handle<v8::Value> new_boxed_string = v8::StringObject::New(the_string);
   CHECK(new_boxed_string->IsStringObject());
   as_boxed = new_boxed_string.As<v8::StringObject>();
   the_string = as_boxed->ValueOf();
   CHECK(!the_string.IsEmpty());
   ExpectObject("\"test\"", the_string);
 }
 
 
+TEST(StringObjectDelete) {
+  LocalContext context;
+  v8::HandleScope scope(context->GetIsolate());
+  v8::Handle<Value> boxed_string = CompileRun("new String(\"test\")");
+  CHECK(boxed_string->IsStringObject());
+  v8::Handle<v8::Object> str_obj = boxed_string.As<v8::Object>();
+  CHECK(!str_obj->Delete(2));
+  CHECK(!str_obj->Delete(v8_num(2)));
+}
+
+
 THREADED_TEST(NumberObject) {
   LocalContext env;
   v8::HandleScope scope(env->GetIsolate());
   v8::Handle<Value> boxed_number = CompileRun("new Number(42)");
   CHECK(boxed_number->IsNumberObject());
   v8::Handle<Value> unboxed_number = CompileRun("42");
   CHECK(!unboxed_number->IsNumberObject());
   v8::Handle<Value> boxed_not_number = CompileRun("new Boolean(false)");
   CHECK(!boxed_not_number->IsNumberObject());
   v8::Handle<v8::NumberObject> as_boxed = boxed_number.As<v8::NumberObject>();
@@ skipping 19514 matching lines @@
   // add the testExtraShouldReturnFive export
   v8::Local<v8::Object> exports = env->GetExtrasExportsObject();
 
   auto func =
       exports->Get(v8_str("testExtraShouldReturnFive")).As<v8::Function>();
   auto undefined = v8::Undefined(isolate);
   auto result = func->Call(undefined, 0, {}).As<v8::Number>();
 
   CHECK(result->Value() == 5.0);
 }