Emit better error message about writable properties

test/mjsunit/messages.js

 // Copyright 2015 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.
 
 // Flags: --stack-size=100 --harmony --harmony-reflect --harmony-regexps
 // Flags: --harmony-simd --strong-mode
 
 function test(f, expected, type) {
   try {
     f();
@@ skipping 314 matching lines @@
 }, "Cannot convert a SIMD value to a number", TypeError);
 
 // kUndefinedOrNullToObject
 test(function() {
   Array.prototype.toString.call(null);
 }, "Cannot convert undefined or null to object", TypeError);
 
 // kValueAndAccessor
 test(function() {
   Object.defineProperty({}, "x", { get: function(){}, value: 1});
-}, "Invalid property.  A property cannot both have accessors and be " +
-   "writable or have a value, #<Object>", TypeError);
+}, "Invalid property descriptor. Cannot both specify accessors " +
+   "and a value or writable attribute, #<Object>", TypeError);
 
 // kWithExpression
 test(function() {
   with (null) {}
 }, "null has no properties", TypeError);
 
 // kWrongArgs
 test(function() {
   (function() {}).apply({}, 1);
 }, "Function.prototype.apply: Arguments list has wrong type", TypeError);
@@ skipping 116 matching lines @@
   Number(1).toString(100);
 }, "toString() radix argument must be between 2 and 36", RangeError);
 
 
 // === URIError ===
 
 // kURIMalformed
 test(function() {
   decodeURI("%%");
 }, "URI malformed", URIError);