Revert of [builtins] Move StringNormalize to a cpp builtin.

src/js/string.js

 // Copyright 2012 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.
 
 (function(global, utils) {
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
@@ skipping 100 matching lines @@
 
   var subject = TO_STRING(this);
 
   // Equivalent to RegExpCreate (ES#sec-regexpcreate)
   var regexp = %_NewObject(GlobalRegExp, GlobalRegExp);
   RegExpInitialize(regexp, pattern);
   return regexp[matchSymbol](subject);
 }
 
 
+// ECMA-262 v6, section 21.1.3.12
+//
+// For now we do nothing, as proper normalization requires big tables.
+// If Intl is enabled, then i18n.js will override it and provide the the
+// proper functionality.
+function StringNormalize(formArg) {  // length == 0
+  CHECK_OBJECT_COERCIBLE(this, "String.prototype.normalize");
+  var s = TO_STRING(this);
+
+  var form = IS_UNDEFINED(formArg) ? 'NFC' : TO_STRING(formArg);
+
+  var NORMALIZATION_FORMS = ['NFC', 'NFD', 'NFKC', 'NFKD'];
+  var normalizationForm = %ArrayIndexOf(NORMALIZATION_FORMS, form, 0);
+  if (normalizationForm === -1) {
+    throw %make_range_error(kNormalizationForm,
+                         %_Call(ArrayJoin, NORMALIZATION_FORMS, ', '));
+  }
+
+  return s;
+}
+
+%FunctionSetLength(StringNormalize, 0);
+
+
 // This has the same size as the RegExpLastMatchInfo array, and can be used
 // for functions that expect that structure to be returned.  It is used when
 // the needle is a string rather than a regexp.  In this case we can't update
 // lastMatchArray without erroneously affecting the properties on the global
 // RegExp object.
 var reusableMatchInfo = [2, "", "", -1, -1];
 
 
 // ES6, section 21.1.3.14
 function StringReplace(search, replace) {
@@ skipping 578 matching lines @@
 // Set up the non-enumerable functions on the String prototype object.
 utils.InstallFunctions(GlobalString.prototype, DONT_ENUM, [
   "codePointAt", StringCodePointAt,
   "concat", StringConcat,
   "endsWith", StringEndsWith,
   "includes", StringIncludes,
   "indexOf", StringIndexOf,
   "lastIndexOf", StringLastIndexOf,
   "localeCompare", StringLocaleCompareJS,
   "match", StringMatchJS,
+  "normalize", StringNormalize,
   "repeat", StringRepeat,
   "replace", StringReplace,
   "search", StringSearch,
   "slice", StringSlice,
   "split", StringSplitJS,
   "substring", StringSubstring,
   "substr", StringSubstr,
   "startsWith", StringStartsWith,
   "toLowerCase", StringToLowerCaseJS,
   "toLocaleLowerCase", StringToLocaleLowerCase,
@@ skipping 24 matching lines @@
   to.StringLastIndexOf = StringLastIndexOf;
   to.StringMatch = StringMatchJS;
   to.StringReplace = StringReplace;
   to.StringSlice = StringSlice;
   to.StringSplit = StringSplitJS;
   to.StringSubstr = StringSubstr;
   to.StringSubstring = StringSubstring;
 });
 
 })