Update ObjectToString to Harmony-draft algorithm

src/bootstrapper.cc

 // Copyright 2014 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.
 
 #include "src/bootstrapper.h"
 
 #include "src/accessors.h"
 #include "src/code-stubs.h"
 #include "src/extensions/externalize-string-extension.h"
 #include "src/extensions/free-buffer-extension.h"
@@ skipping 2070 matching lines @@
 
 bool Genesis::InstallExperimentalNatives() {
   for (int i = ExperimentalNatives::GetDebuggerCount();
        i < ExperimentalNatives::GetBuiltinsCount();
        i++) {
     INSTALL_EXPERIMENTAL_NATIVE(i, proxies, "proxy.js")
     INSTALL_EXPERIMENTAL_NATIVE(i, strings, "harmony-string.js")
     INSTALL_EXPERIMENTAL_NATIVE(i, arrays, "harmony-array.js")
     INSTALL_EXPERIMENTAL_NATIVE(i, arrays, "harmony-typedarray.js")
     INSTALL_EXPERIMENTAL_NATIVE(i, classes, "harmony-classes.js")
+    INSTALL_EXPERIMENTAL_NATIVE(i, tostring, "harmony-tostring.js")
   }
 
   InstallExperimentalNativeFunctions();
   return true;
 }
 
 
 static void InstallBuiltinFunctionId(Handle<JSObject> holder,
                                      const char* function_name,
                                      BuiltinFunctionId id) {
@@ skipping 613 matching lines @@
   return from + sizeof(NestingCounterType);
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   DCHECK(!IsActive());
 }
 
 } }  // namespace v8::internal