Keep a persistent handle for the bindings classes to avoid repeated lookups that involve performing…

Source/bindings/dart/custom/DartWindowCustom.cpp

 // Copyright 2011, Google Inc.
 // 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
@@ skipping 51 matching lines @@
     // FIXME: proper implementation.
     DART_UNIMPLEMENTED();
 }
 
 void historyCrossFrameGetter(Dart_NativeArguments args)
 {
     {
         DOMWindow* receiver = DartDOMWrapper::receiver<DOMWindow>(args);
 
         Dart_Handle result = DartDOMWrapper::toDartWithClassName<DartHistory>(
-            receiver->history(), "_HistoryCrossFrame", DartUtilities::htmlLibraryName);
+            receiver->history(), "_HistoryCrossFrame", DartUtilities::htmlLibraryName, _HistoryCrossFrameClassId);
         if (result)
             Dart_SetReturnValue(args, result);
     }
 }
 
 void locationCrossFrameGetter(Dart_NativeArguments args)
 {
     {
         DOMWindow* receiver = DartDOMWrapper::receiver<DOMWindow>(args);
 
         Dart_Handle result = DartDOMWrapper::toDartWithClassName<DartLocation>(
-            receiver->location(), "_LocationCrossFrame", DartUtilities::htmlLibraryName);
+            receiver->location(), "_LocationCrossFrame", DartUtilities::htmlLibraryName, _LocationCrossFrameClassId);
         if (result)
             Dart_SetReturnValue(args, result);
     }
 }
 
 void locationSetter(Dart_NativeArguments args)
 {
     Dart_Handle exception = 0;
     {
         DOMWindow* receiver = DartDOMWrapper::receiver<DOMWindow>(args);
@@ skipping 203 matching lines @@
 void ___getter___2Callback(Dart_NativeArguments)
 {
     // FIXME: proper implementation.
     DART_UNIMPLEMENTED();
 }
 
 }
 
 Dart_Handle DartWindow::toDart(DOMWindow* window)
 {
-    return DartDOMWrapper::toDartWithClassName<DartWindow>(window, "_DOMWindowCrossFrame", DartUtilities::htmlLibraryName);
+    return DartDOMWrapper::toDartWithClassName<DartWindow>(window, "_DOMWindowCrossFrame", DartUtilities::htmlLibraryName, _DOMWindowCrossFrameClassId);
 }
 
 }