[builtins] Migrate String.prototype.trim/trimLeft/trimRight to C++.

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 500 matching lines @@
 }
 
 
 // ECMA-262, 15.5.4.19
 function StringToLocaleUpperCase() {
   CHECK_OBJECT_COERCIBLE(this, "String.prototype.toLocaleUpperCase");
 
   return %StringToUpperCase(TO_STRING(this));
 }
 
-// ES5, 15.5.4.20
-function StringTrimJS() {
-  CHECK_OBJECT_COERCIBLE(this, "String.prototype.trim");
-
-  return %StringTrim(TO_STRING(this), true, true);
-}
-
-function StringTrimLeft() {
-  CHECK_OBJECT_COERCIBLE(this, "String.prototype.trimLeft");
-
-  return %StringTrim(TO_STRING(this), true, false);
-}
-
-function StringTrimRight() {
-  CHECK_OBJECT_COERCIBLE(this, "String.prototype.trimRight");
-
-  return %StringTrim(TO_STRING(this), false, true);
-}
-
 
 // ES6 draft, revision 26 (2014-07-18), section B.2.3.2.1
 function HtmlEscape(str) {
   return %_Call(StringReplace, TO_STRING(str), /"/g, """);
 }
 
 
 // ES6 draft, revision 26 (2014-07-18), section B.2.3.2
 function StringAnchor(name) {
   CHECK_OBJECT_COERCIBLE(this, "String.prototype.anchor");
@@ skipping 293 matching lines @@
   "search", StringSearch,
   "slice", StringSlice,
   "split", StringSplitJS,
   "substring", StringSubstring,
   "substr", StringSubstr,
   "startsWith", StringStartsWith,
   "toLowerCase", StringToLowerCaseJS,
   "toLocaleLowerCase", StringToLocaleLowerCase,
   "toUpperCase", StringToUpperCaseJS,
   "toLocaleUpperCase", StringToLocaleUpperCase,
-  "trim", StringTrimJS,
-  "trimLeft", StringTrimLeft,
-  "trimRight", StringTrimRight,
 
   "link", StringLink,
   "anchor", StringAnchor,
   "fontcolor", StringFontcolor,
   "fontsize", StringFontsize,
   "big", StringBig,
   "blink", StringBlink,
   "bold", StringBold,
   "fixed", StringFixed,
   "italics", StringItalics,
@@ skipping 12 matching lines @@
   to.StringLastIndexOf = StringLastIndexOf;
   to.StringMatch = StringMatchJS;
   to.StringReplace = StringReplace;
   to.StringSlice = StringSlice;
   to.StringSplit = StringSplitJS;
   to.StringSubstr = StringSubstr;
   to.StringSubstring = StringSubstring;
 });
 
 })