[stubs] Unify (and optimize) implementation of ToObject.

src/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 1094 matching lines @@
 }
 
 
 // -------------------------------------------------------------------
 // String methods related to templates
 
 // ES6 Draft 03-17-2015, section 21.1.2.4
 function StringRaw(callSite) {
   // TODO(caitp): Use rest parameters when implemented
   var numberOfSubstitutions = %_ArgumentsLength();
-  var cooked = $toObject(callSite);
-  var raw = $toObject(cooked.raw);
+  var cooked = TO_OBJECT(callSite);
+  var raw = TO_OBJECT(cooked.raw);
   var literalSegments = $toLength(raw.length);
   if (literalSegments <= 0) return "";
 
   var result = $toString(raw[0]);
 
   for (var i = 1; i < literalSegments; ++i) {
     if (i < numberOfSubstitutions) {
       result += $toString(%_Arguments(i));
     }
     result += $toString(raw[i]);
@@ skipping 73 matching lines @@
   to.StringIndexOf = StringIndexOfJS;
   to.StringLastIndexOf = StringLastIndexOfJS;
   to.StringMatch = StringMatchJS;
   to.StringReplace = StringReplace;
   to.StringSplit = StringSplitJS;
   to.StringSubstr = StringSubstr;
   to.StringSubstring = StringSubstring;
 });
 
 })