Revert of [builtins] Move StringIncludes to a 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 415 matching lines @@
   if (start < 0) {
     return false;
   }
 
   return %_SubString(s, start, start + ss_len) === ss;
 }
 
 %FunctionSetLength(StringEndsWith, 1);
 
 
+// ES6 draft 04-05-14, section 21.1.3.6
+function StringIncludes(searchString, position) {  // length == 1
+  CHECK_OBJECT_COERCIBLE(this, "String.prototype.includes");
+
+  var string = TO_STRING(this);
+
+  if (IsRegExp(searchString)) {
+    throw %make_type_error(kFirstArgumentNotRegExp, "String.prototype.includes");
+  }
+
+  searchString = TO_STRING(searchString);
+  var pos = TO_INTEGER(position);
+
+  var stringLength = string.length;
+  if (pos < 0) pos = 0;
+  if (pos > stringLength) pos = stringLength;
+  var searchStringLength = searchString.length;
+
+  if (searchStringLength + pos > stringLength) {
+    return false;
+  }
+
+  return %StringIndexOf(string, searchString, pos) !== -1;
+}
+
+%FunctionSetLength(StringIncludes, 1);
+
+
 // ES6 Draft 05-22-2014, section 21.1.3.3
 function StringCodePointAt(pos) {
   CHECK_OBJECT_COERCIBLE(this, "String.prototype.codePointAt");
 
   var string = TO_STRING(this);
   var size = string.length;
   pos = TO_INTEGER(pos);
   if (pos < 0 || pos >= size) {
     return UNDEFINED;
   }
@@ skipping 38 matching lines @@
 // Set up the non-enumerable functions on the String object.
 utils.InstallFunctions(GlobalString, DONT_ENUM, [
   "raw", StringRaw
 ]);
 
 // 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,
   "match", StringMatchJS,
   "repeat", StringRepeat,
   "replace", StringReplace,
   "search", StringSearch,
   "slice", StringSlice,
   "split", StringSplitJS,
   "startsWith", StringStartsWith,
   "toLowerCase", StringToLowerCaseJS,
   "toLocaleLowerCase", StringToLocaleLowerCase,
   "toUpperCase", StringToUpperCaseJS,
@@ skipping 18 matching lines @@
 // Exports
 
 utils.Export(function(to) {
   to.StringMatch = StringMatchJS;
   to.StringReplace = StringReplace;
   to.StringSlice = StringSlice;
   to.StringSplit = StringSplitJS;
 });
 
 })