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

Source/bindings/dart/custom/DartWindowCustom.cpp

Index: Source/bindings/dart/custom/DartWindowCustom.cpp
diff --git a/Source/bindings/dart/custom/DartWindowCustom.cpp b/Source/bindings/dart/custom/DartWindowCustom.cpp
index 215bda4cffb53f9857c0f76ddb470e045dd60d29..978711173a35f6b8ba5202979bb20779056bcf7d 100644
--- a/Source/bindings/dart/custom/DartWindowCustom.cpp
+++ b/Source/bindings/dart/custom/DartWindowCustom.cpp
@@ -69,7 +69,7 @@ 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);
     }
@@ -81,7 +81,7 @@ 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);
     }
@@ -305,7 +305,7 @@ void ___getter___2Callback(Dart_NativeArguments)
 
 Dart_Handle DartWindow::toDart(DOMWindow* window)
 {
-    return DartDOMWrapper::toDartWithClassName<DartWindow>(window, "_DOMWindowCrossFrame", DartUtilities::htmlLibraryName);
+    return DartDOMWrapper::toDartWithClassName<DartWindow>(window, "_DOMWindowCrossFrame", DartUtilities::htmlLibraryName, _DOMWindowCrossFrameClassId);
 }
 
 }