Cutover v8 to use new style callbacks internally

src/extensions/externalize-string-extension.h

Index: src/extensions/externalize-string-extension.h
diff --git a/src/extensions/externalize-string-extension.h b/src/extensions/externalize-string-extension.h
index b97b4962cf0b20f4fba15f0175a52201dc233438..ecbc1cf447c47ac5c99262371c0950b7eae35267 100644
--- a/src/extensions/externalize-string-extension.h
+++ b/src/extensions/externalize-string-extension.h
@@ -38,8 +38,8 @@ class ExternalizeStringExtension : public v8::Extension {
   ExternalizeStringExtension() : v8::Extension("v8/externalize", kSource) {}
   virtual v8::Handle<v8::FunctionTemplate> GetNativeFunction(
       v8::Handle<v8::String> name);
-  static v8::Handle<v8::Value> Externalize(const v8::Arguments& args);
-  static v8::Handle<v8::Value> IsAscii(const v8::Arguments& args);
+  static void Externalize(const v8::FunctionCallbackInfo<v8::Value>& args);
+  static void IsAscii(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void Register();
  private:
   static const char* const kSource;