- Change access pattern to Native Arguments (make one call instead of two).

tools/dom/templates/html/dartium/cpp_callback_header.template

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // WARNING: Do not edit - generated code.
 
 #ifndef Dart$(INTERFACE)_h
 #define Dart$(INTERFACE)_h
 
 #include "bindings/v8/ActiveDOMCallback.h"
@@ skipping 11 matching lines @@
     {
         return adoptRef(new Dart$(INTERFACE)(object, exception, DartUtilities::scriptExecutionContext()));
     }
 
     static PassRefPtr<NativeType> createWithNullCheck(Dart_Handle object, Dart_Handle& exception)
     {
         if (Dart_IsNull(object))
             return 0;
         return create(object, exception);
     }
+
+    static PassRefPtr<NativeType> create(Dart_NativeArguments args, int idx, Dart_Handle& exception)
+    {
+        Dart_Handle object = Dart_GetNativeArgument(args, idx);
+        return create(object, exception);
+    }
+
+    static PassRefPtr<NativeType> createWithNullCheck(Dart_NativeArguments args, int idx, Dart_Handle& exception)
+    {
+        Dart_Handle object = Dart_GetNativeArgument(args, idx);
+        if (Dart_IsNull(object))
+            return 0;
+        return create(object, exception);
+    }
+
 $HANDLERS
 
 private:
     Dart$(INTERFACE)(Dart_Handle object, Dart_Handle& exception, ScriptExecutionContext* context)
         : ActiveDOMCallback(context)
         , m_callback(object, exception)
     {
     }
 
     DartCallback m_callback;
 };
 
 }
 
 #endif // Dart$(INTERFACE)_h