[runtime] Remove useless DELETE builtin.

src/runtime/runtime-object.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/v8.h"
 
 #include "src/arguments.h"
 #include "src/bootstrapper.h"
 #include "src/debug/debug.h"
 #include "src/messages.h"
@@ skipping 653 matching lines @@
   LanguageMode language_mode = language_mode_arg;
 
   Handle<Object> result;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
       isolate, result,
       Runtime::SetObjectProperty(isolate, object, key, value, language_mode));
   return *result;
 }
 
 
-RUNTIME_FUNCTION(Runtime_DeleteProperty) {
-  HandleScope scope(isolate);
-  DCHECK(args.length() == 3);
-  CONVERT_ARG_HANDLE_CHECKED(JSReceiver, receiver, 0);
-  CONVERT_ARG_HANDLE_CHECKED(Object, key, 1);
-  CONVERT_LANGUAGE_MODE_ARG_CHECKED(language_mode, 2);
+namespace {
+
+// ES6 section 12.5.4.
+Object* DeleteProperty(Isolate* isolate, Handle<Object> object,
+                       Handle<Object> key, LanguageMode language_mode) {
+  Handle<JSReceiver> receiver;
+  if (!JSReceiver::ToObject(isolate, object).ToHandle(&receiver)) {
+    THROW_NEW_ERROR_RETURN_FAILURE(
+        isolate, NewTypeError(MessageTemplate::kUndefinedOrNullToObject));
+  }
   Handle<Object> result;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
       isolate, result,
       Runtime::DeleteObjectProperty(isolate, receiver, key, language_mode));
   return *result;
 }
 
+}  // namespace
+
+
+RUNTIME_FUNCTION(Runtime_DeleteProperty_Sloppy) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(2, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(Object, object, 0);
+  CONVERT_ARG_HANDLE_CHECKED(Object, key, 1);
+  return DeleteProperty(isolate, object, key, SLOPPY);
+}
+
+
+RUNTIME_FUNCTION(Runtime_DeleteProperty_Strict) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(2, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(Object, object, 0);
+  CONVERT_ARG_HANDLE_CHECKED(Object, key, 1);
+  return DeleteProperty(isolate, object, key, STRICT);
+}
+
 
 static Object* HasOwnPropertyImplementation(Isolate* isolate,
                                             Handle<JSObject> object,
                                             Handle<Name> key) {
   Maybe<bool> maybe = JSReceiver::HasOwnProperty(object, key);
   if (!maybe.IsJust()) return isolate->heap()->exception();
   if (maybe.FromJust()) return isolate->heap()->true_value();
   // Handle hidden prototypes.  If there's a hidden prototype above this thing
   // then we have to check it for properties, because they are supposed to
   // look like they are on this object.
@@ skipping 740 matching lines @@
   Handle<JSReceiver> receiver;
   if (JSReceiver::ToObject(isolate, object).ToHandle(&receiver)) {
     return *receiver;
   }
   THROW_NEW_ERROR_RETURN_FAILURE(
       isolate, NewTypeError(MessageTemplate::kUndefinedOrNullToObject));
 }
 
 }  // namespace internal
 }  // namespace v8