Make sure that data functions return 0 instead of -0 for a number of...

src/date-delay.js

 // Copyright 2006-2008 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 32 matching lines @@
 
 // ECMA 262 - 15.9.1.2
 function Day(time) {
   return FLOOR(time/msPerDay);
 }
 
 
 // ECMA 262 - 5.2
 function Modulo(value, remainder) {
   var mod = value % remainder;
+  // Guard against returning -0.
+  if (mod == 0) return 0;
   return mod >= 0 ? mod : mod + remainder;
 }
 
 
 function TimeWithinDay(time) {
   return Modulo(time, msPerDay);
 }
 
 
 // ECMA 262 - 15.9.1.3
@@ skipping 963 matching lines @@
     "setFullYear", DateSetFullYear,
     "setUTCFullYear", DateSetUTCFullYear,
     "toGMTString", DateToGMTString,
     "toUTCString", DateToUTCString,
     "getYear", DateGetYear,
     "setYear", DateSetYear
   ));
 }
 
 SetupDate();