Make date parser handle all ES5 Date Time Strings correctly.

src/date.js

Index: src/date.js
diff --git a/src/date.js b/src/date.js
index 5a2e9a2343f0b911518f3a44ccd10ebc8079c54b..79b846d4a7060efc938990330cf8396b07224073 100644
--- a/src/date.js
+++ b/src/date.js
@@ -981,11 +981,22 @@ function PadInt(n, digits) {
 function DateToISOString() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return kInvalidDate;
-  return this.getUTCFullYear() + 
+  var year = this.getUTCFullYear();
+  var year_string;
+  if (year >= 0 && year <= 9999) {
+    year_string = PadInt(year, 4);
+  } else {
+    if (year < 0) {
+      year_string = "-" + PadInt(-year, 6);
+    } else {
+      year_string = "+" + PadInt(year, 6);
+    }
+  }
+  return year_string +
       '-' + PadInt(this.getUTCMonth() + 1, 2) +
-      '-' + PadInt(this.getUTCDate(), 2) + 
+      '-' + PadInt(this.getUTCDate(), 2) +
       'T' + PadInt(this.getUTCHours(), 2) +
-      ':' + PadInt(this.getUTCMinutes(), 2) + 
+      ':' + PadInt(this.getUTCMinutes(), 2) +
       ':' + PadInt(this.getUTCSeconds(), 2) +
       '.' + PadInt(this.getUTCMilliseconds(), 3) +
       'Z';
@@ -995,8 +1006,8 @@ function DateToISOString() {
 function DateToJSON(key) {
   var o = ToObject(this);
   var tv = DefaultNumber(o);
-  if (IS_NUMBER(tv) && !NUMBER_IS_FINITE(tv)) { 
-    return null; 
+  if (IS_NUMBER(tv) && !NUMBER_IS_FINITE(tv)) {
+    return null;
   }
   return o.toISOString();
 }