Test that trailing commas in object literals are allowed

src/preparser.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.
 
 #ifndef V8_PREPARSER_H
 #define V8_PREPARSER_H
 
 #include "src/v8.h"
 
 #include "src/func-name-inferrer.h"
@@ skipping 1525 matching lines @@
 
 
 template <class Traits>
 typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseObjectLiteral(
     bool* ok) {
   // ObjectLiteral ::
   // '{' ((
   //       ((IdentifierName | String | Number) ':' AssignmentExpression) |
   //       (('get' | 'set') (IdentifierName | String | Number) FunctionLiteral)
   //      ) ',')* '}'
-  // (Except that trailing comma is not required and not allowed.)
+  // (Except that the trailing comma is not required.)
 
   int pos = peek_position();
   typename Traits::Type::PropertyList properties =
       this->NewPropertyList(4, zone_);
   int number_of_boilerplate_properties = 0;
   bool has_function = false;
 
   ObjectLiteralChecker checker(this, strict_mode());
 
   Expect(Token::LBRACE, CHECK_OK);
@@ skipping 110 matching lines @@
     // property. (Parser only.)
     this->CheckFunctionLiteralInsideTopLevelObjectLiteral(scope_, value,
                                                           &has_function);
 
     // Count CONSTANT or COMPUTED properties to maintain the enumeration order.
     if (this->IsBoilerplateProperty(property)) {
       number_of_boilerplate_properties++;
     }
     properties->Add(property, zone());
 
     // TODO(1240767): Consider allowing trailing comma.

[marja, 2014/06/25 10:04:00]

Pls remove this TODO.

     if (peek() != Token::RBRACE) {
       // Need {} because of the CHECK_OK macro.
       Expect(Token::COMMA, CHECK_OK);
     }
 
     if (fni_ != NULL) {
       fni_->Infer();
       fni_->Leave();
     }
   }
@@ skipping 519 matching lines @@
       parser()->ReportMessage("accessor_get_set");
     }
     *ok = false;
   }
 }
 
 
 } }  // v8::internal
 
 #endif  // V8_PREPARSER_H