Add support for DateTimeFormat.formatToParts

src/js/i18n.js

 // Copyright 2013 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.
 
 // ECMAScript 402 API implementation.
 
 /**
  * Intl object is a single object that has some named properties,
  * all of which are constructors.
  */
@@ skipping 1779 matching lines @@
   } else {
     dateMs = TO_NUMBER(dateValue);
   }
 
   if (!NUMBER_IS_FINITE(dateMs)) throw %make_range_error(kDateRange);
 
   return %InternalDateFormat(%GetImplFromInitializedIntlObject(formatter),
                              new GlobalDate(dateMs));
 }
 
+function FormatDateToParts(dateValue) {
+  if (!IS_UNDEFINED(new.target)) {
+    throw %make_type_error(kOrdinaryFunctionCalledAsConstructor);
+  }
+  CHECK_OBJECT_COERCIBLE(this, "Intl.DateTimeFormat.prototype.formatToParts");
+  if (!IS_OBJECT(this)) {
+    throw %make_type_error(kCalledOnNonObject, this);
+  }
+  var dateMs;
+  if (IS_UNDEFINED(dateValue)) {
+    dateMs = %DateCurrentTime();
+  } else {
+    dateMs = TO_NUMBER(dateValue);
+  }
+
+  if (!NUMBER_IS_FINITE(dateMs)) throw %make_range_error(kDateRange);
+
+  return %InternalDateFormatToParts(
+      %GetImplFromInitializedIntlObject(this), new GlobalDate(dateMs));
+}
+
+%FunctionSetLength(FormatDateToParts, 0);
+
 
 /**
  * Returns a Date object representing the result of calling ToString(value)
  * according to the effective locale and the formatting options of this
  * DateTimeFormat.
  * Returns undefined if date string cannot be parsed.
  */
 function IntlParseDate(formatter, value) {
   return %InternalDateParse(%GetImplFromInitializedIntlObject(formatter),
                             TO_STRING(value));
@@ skipping 474 matching lines @@
       throw %make_type_error(kOrdinaryFunctionCalledAsConstructor);
     }
 
     var locales = arguments[0];
     var options = arguments[1];
     return toLocaleDateTime(
         this, locales, options, 'time', 'time', 'dateformattime');
   }
 );
 
+%FunctionRemovePrototype(FormatDateToParts);
+
 utils.Export(function(to) {
   to.AddBoundMethod = AddBoundMethod;
+  to.FormatDateToParts = FormatDateToParts;
   to.IntlParseDate = IntlParseDate;
   to.IntlParseNumber = IntlParseNumber;
 });
 
 })