Add trim, trimLeft and trimRight methods to String

src/string.js

 // Copyright 2006-2008 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 662 matching lines @@
 function StringToUpperCase() {
   return %StringToUpperCase(ToString(this));
 }
 
 
 // ECMA-262, 15.5.4.19
 function StringToLocaleUpperCase() {
   return %StringToUpperCase(ToString(this));
 }
 
+// ES5, 15.5.4.20
+function StringTrim() {
+  return %StringTrim(ToString(this), true, true);
+}
+
+function StringTrimLeft() {
+  return %StringTrim(ToString(this), true, false);
+}
+
+function StringTrimRight() {
+  return %StringTrim(ToString(this), false, true);
+}
 
 // ECMA-262, section 15.5.3.2
 function StringFromCharCode(code) {
   var n = %_ArgumentsLength();
   if (n == 1) return %CharFromCode(ToNumber(code) & 0xffff)
 
   // NOTE: This is not super-efficient, but it is necessary because we
   // want to avoid converting to numbers from within the virtual
   // machine. Maybe we can find another way of doing this?
   var codes = new $Array(n);
@@ skipping 155 matching lines @@
     "replace", StringReplace,
     "search", StringSearch,
     "slice", StringSlice,
     "split", StringSplit,
     "substring", StringSubstring,
     "substr", StringSubstr,
     "toLowerCase", StringToLowerCase,
     "toLocaleLowerCase", StringToLocaleLowerCase,
     "toUpperCase", StringToUpperCase,
     "toLocaleUpperCase", StringToLocaleUpperCase,
+    "trim", StringTrim,
+    "trimLeft", StringTrimLeft,
+    "trimRight", StringTrimRight,
     "link", StringLink,
     "anchor", StringAnchor,
     "fontcolor", StringFontcolor,
     "fontsize", StringFontsize,
     "big", StringBig,
     "blink", StringBlink,
     "bold", StringBold,
     "fixed", StringFixed,
     "italics", StringItalics,
     "small", StringSmall,
     "strike", StringStrike,
     "sub", StringSub,
     "sup", StringSup,
     "toJSON", StringToJSON
   ));
 }
 
 
 SetupString();