Move helper methods from i18n extension into runtime.

src/extensions/i18n/locale.js

 // Copyright 2013 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 16 matching lines @@
 // limitations under the License.
 
 // ECMAScript 402 API implementation is broken into separate files for
 // each service. The build system combines them together into one
 // Intl namespace.
 
 /**
  * Canonicalizes the language tag, or throws in case the tag is invalid.
  */
 function canonicalizeLanguageTag(localeID) {
-  native function NativeJSCanonicalizeLanguageTag();
-
   // null is typeof 'object' so we have to do extra check.
   if (typeof localeID !== 'string' && typeof localeID !== 'object' ||
       localeID === null) {
     throw new TypeError('Language ID should be string or object.');
   }
 
   var localeString = String(localeID);
 
   if (isValidLanguageTag(localeString) === false) {
     throw new RangeError('Invalid language tag: ' + localeString);
   }
 
   // This call will strip -kn but not -kn-true extensions.
   // ICU bug filled - http://bugs.icu-project.org/trac/ticket/9265.
   // TODO(cira): check if -u-kn-true-kc-true-kh-true still throws after
   // upgrade to ICU 4.9.
-  var tag = NativeJSCanonicalizeLanguageTag(localeString);
+  var tag = %CanonicalizeLanguageTag(localeString);
   if (tag === 'invalid-tag') {
     throw new RangeError('Invalid language tag: ' + localeString);
   }
 
   return tag;
 }
 
 
 /**
  * Returns an array where all locales are canonicalized and duplicates removed.
@@ skipping 117 matching lines @@
   var extLang = '(' + alpha + '{3}(-' + alpha + '{3}){0,2})';
   var language = '(' + alpha + '{2,3}(-' + extLang + ')?|' + alpha + '{4}|' +
                  alpha + '{5,8})';
   var langTag = language + '(-' + script + ')?(-' + region + ')?(-' +
                 variant + ')*(-' + extension + ')*(-' + privateUse + ')?';
 
   var languageTag =
       '^(' + langTag + '|' + privateUse + '|' + grandfathered + ')$';
   LANGUAGE_TAG_RE = new RegExp(languageTag, 'i');
 })();